7977526489 has 3 divisors (see below), whose sum is σ = 7977615807. Its totient is φ = 7977437172.

The previous prime is 7977526483. The next prime is 7977526493. The reversal of 7977526489 is 9846257797.

The square root of 7977526489 is 89317.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 3313729225 + 4663797264 = 57565^2 + 68292^2 .

It is not a de Polignac number, because 7977526489 - 2¹¹ = 7977524441 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 7977526489.

It is not an unprimeable number, because it can be changed into a prime (7977526483) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 44659 + ... + 133975.

It is an arithmetic number, because the mean of its divisors is an integer number (2659205269).

Almost surely, 2^7977526489 is an apocalyptic number.

7977526489 is the 89317-th square number.

7977526489 is the 44659-th centered octagonal number.

It is an amenable number.

7977526489 is a deficient number, since it is larger than the sum of its proper divisors (89318).

7977526489 is an frugal number, since it uses more digits than its factorization.

7977526489 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 178634 (or 89317 counting only the distinct ones).

The product of its digits is 53343360, while the sum is 64.

The cubic root of 7977526489 is about 1998.1254509986.

Multiplying 7977526489 by its sum of digits (64), we get a square (510561695296 = 714536²).

It can be divided in two parts, 7977526 and 489, that added together give a triangular number (7978015 = T₃₉₉₄).

The spelling of 7977526489 in words is "seven billion, nine hundred seventy-seven million, five hundred twenty-six thousand, four hundred eighty-nine".