76440561 has 4 divisors (see below), whose sum is σ = 101920752. Its totient is φ = 50960372.

The previous prime is 76440509. The next prime is 76440571. The reversal of 76440561 is 16504467.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 76440561 - 2¹⁴ = 76424177 is a prime.

It is not an unprimeable number, because it can be changed into a prime (76440571) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12740091 + ... + 12740096.

It is an arithmetic number, because the mean of its divisors is an integer number (25480188).

Almost surely, 2^76440561 is an apocalyptic number.

It is an amenable number.

76440561 is a deficient number, since it is larger than the sum of its proper divisors (25480191).

76440561 is a wasteful number, since it uses less digits than its factorization.

76440561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25480190.

The product of its (nonzero) digits is 20160, while the sum is 33.

The square root of 76440561 is about 8743.0292805183. The cubic root of 76440561 is about 424.3992638335.

It can be divided in two parts, 764405 and 61, that added together give a triangular number (764466 = T₁₂₃₆).

The spelling of 76440561 in words is "seventy-six million, four hundred forty thousand, five hundred sixty-one".