3656021856 has 48 divisors (see below), whose sum is σ = 10014326784. Its totient is φ = 1165687424.

The previous prime is 3656021849. The next prime is 3656021861. The reversal of 3656021856 is 6581206563.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (48).

It is a hoax number, since the sum of its digits (42) coincides with the sum of the digits of its distinct prime factors.

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, 825696 + ... + 830111.

It is an arithmetic number, because the mean of its divisors is an integer number (208631808).

Almost surely, 2^3656021856 is an apocalyptic number.

It is an amenable number.

3656021856 is an abundant number, since it is smaller than the sum of its proper divisors (6358304928).

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

3656021856 is a wasteful number, since it uses less digits than its factorization.

3656021856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1655843 (or 1655835 counting only the distinct ones).

The product of its (nonzero) digits is 259200, while the sum is 42.

The square root of 3656021856 is about 60465.0465641101. The cubic root of 3656021856 is about 1540.5279934647.

The spelling of 3656021856 in words is "three billion, six hundred fifty-six million, twenty-one thousand, eight hundred fifty-six".