406021656 has 32 divisors (see below), whose sum is σ = 1024043760. Its totient is φ = 134141952.

The previous prime is 406021643. The next prime is 406021661. The reversal of 406021656 is 656120604.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 72145 + ... + 77568.

Almost surely, 2^406021656 is an apocalyptic number.

It is an amenable number.

406021656 is an abundant number, since it is smaller than the sum of its proper divisors (618022104).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

406021656 is a wasteful number, since it uses less digits than its factorization.

406021656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 149835 (or 149831 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 30.

The square root of 406021656 is about 20149.9790570611. The cubic root of 406021656 is about 740.4852283871.

The spelling of 406021656 in words is "four hundred six million, twenty-one thousand, six hundred fifty-six".