1990904028656 has 20 divisors (see below), whose sum is σ = 3868822787232. Its totient is φ = 992498148096.

The previous prime is 1990904028623. The next prime is 1990904028677. The reversal of 1990904028656 is 6568204090991.

It is a junction number, because it is equal to n+sod(n) for n = 1990904028595 and 1990904028604.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 184611080 + ... + 184621863.

Almost surely, 2^{1990904028656} is an apocalyptic number.

1990904028656 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1990904028656 is a deficient number, since it is larger than the sum of its proper divisors (1877918758576).

1990904028656 is a wasteful number, since it uses less digits than its factorization.

1990904028656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 369233288 (or 369233282 counting only the distinct ones).

The product of its (nonzero) digits is 8398080, while the sum is 59.

The spelling of 1990904028656 in words is "one trillion, nine hundred ninety billion, nine hundred four million, twenty-eight thousand, six hundred fifty-six".