61571970769 has 3 divisors (see below), whose sum is σ = 61572218907. Its totient is φ = 61571722632.

The previous prime is 61571970767. The next prime is 61571970793. The reversal of 61571970769 is 96707917516.

The square root of 61571970769 is 248137.

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., 54767700625 + 6804270144 = 234025^2 + 82488^2 .

It is not a de Polignac number, because 61571970769 - 2¹ = 61571970767 is a prime.

It is a super-2 number, since 2×61571970769² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61571970767) 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, 124069 + ... + 372205.

It is an arithmetic number, because the mean of its divisors is an integer number (20524072969).

Almost surely, 2^61571970769 is an apocalyptic number.

61571970769 is the 248137-th square number.

61571970769 is the 124069-th centered octagonal number.

It is an amenable number.

61571970769 is a deficient number, since it is larger than the sum of its proper divisors (248138).

61571970769 is an frugal number, since it uses more digits than its factorization.

61571970769 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 496274 (or 248137 counting only the distinct ones).

The product of its (nonzero) digits is 5000940, while the sum is 58.

The spelling of 61571970769 in words is "sixty-one billion, five hundred seventy-one million, nine hundred seventy thousand, seven hundred sixty-nine".