88405723561 has 9 divisors (see below), whose sum is σ = 93309510231. Its totient is φ = 83747438784.

The previous prime is 88405723547. The next prime is 88405723579. The reversal of 88405723561 is 16532750488.

It is a happy number.

The square root of 88405723561 is 297331.

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

It can be written as a sum of positive squares in only one way, i.e., 14791181161 + 73614542400 = 121619^2 + 271320^2 .

It is not a de Polignac number, because 88405723561 - 2¹³ = 88405715369 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (88405723531) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 5641465 + ... + 5657113.

It is an arithmetic number, because the mean of its divisors is an integer number (10367723359).

Almost surely, 2^88405723561 is an apocalyptic number.

88405723561 is the 297331-st square number.

88405723561 is the 148666-th centered octagonal number.

It is an amenable number.

88405723561 is a deficient number, since it is larger than the sum of its proper divisors (4903786670).

88405723561 is an frugal number, since it uses more digits than its factorization.

88405723561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31336 (or 15668 counting only the distinct ones).

The product of its (nonzero) digits is 1612800, while the sum is 49.

Multiplying 88405723561 by its sum of digits (49), we get a square (4331880454489 = 2081317²).

The spelling of 88405723561 in words is "eighty-eight billion, four hundred five million, seven hundred twenty-three thousand, five hundred sixty-one".