406556557 has 4 divisors (see below), whose sum is σ = 443516256. Its totient is φ = 369596860.

The previous prime is 406556543. The next prime is 406556561. The reversal of 406556557 is 755655604.

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 a de Polignac number, because none of the positive numbers 2^k-406556557 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (406556567) 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, 18479833 + ... + 18479854.

It is an arithmetic number, because the mean of its divisors is an integer number (110879064).

Almost surely, 2^406556557 is an apocalyptic number.

It is an amenable number.

406556557 is a deficient number, since it is larger than the sum of its proper divisors (36959699).

406556557 is a wasteful number, since it uses less digits than its factorization.

406556557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36959698.

The product of its (nonzero) digits is 630000, while the sum is 43.

The square root of 406556557 is about 20163.2476798754. The cubic root of 406556557 is about 740.8102623462.

The spelling of 406556557 in words is "four hundred six million, five hundred fifty-six thousand, five hundred fifty-seven".