406788561 has 33 divisors (see below), whose sum is σ = 617619529. Its totient is φ = 267924996.

The previous prime is 406788527. The next prime is 406788583. The reversal of 406788561 is 165887604.

It is a happy number.

The square root of 406788561 is 20169.

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

406788561 is a `hidden beast` number, since 4 + 0 + 6 + 7 + 88 + 561 = 666.

It is not a de Polignac number, because 406788561 - 2²⁵ = 373234129 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (406788521) by changing a digit.

It is a polite number, since it can be written in 32 ways as a sum of consecutive naturals, for example, 4901026 + ... + 4901108.

Almost surely, 2^406788561 is an apocalyptic number.

406788561 is the 20169-th square number.

406788561 is the 10085-th centered octagonal number.

It is an amenable number.

406788561 is a deficient number, since it is larger than the sum of its proper divisors (210830968).

406788561 is an frugal number, since it uses more digits than its factorization.

406788561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 196 (or 86 counting only the distinct ones).

The product of its (nonzero) digits is 322560, while the sum is 45.

The cubic root of 406788561 is about 740.9511515275.

The spelling of 406788561 in words is "four hundred six million, seven hundred eighty-eight thousand, five hundred sixty-one".