1656390998 has 16 divisors (see below), whose sum is σ = 2526800640. Its totient is φ = 814240296.

The previous prime is 1656390997. The next prime is 1656391001. The reversal of 1656390998 is 8990936561.

It is a super-2 number, since 2×1656390998² = 5487262276510872008, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1656390991) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 290 + ... + 57557.

It is an arithmetic number, because the mean of its divisors is an integer number (157925040).

Almost surely, 2^1656390998 is an apocalyptic number.

1656390998 is a deficient number, since it is larger than the sum of its proper divisors (870409642).

1656390998 is a wasteful number, since it uses less digits than its factorization.

1656390998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58091.

The product of its (nonzero) digits is 3149280, while the sum is 56.

The square root of 1656390998 is about 40698.7837410407. The cubic root of 1656390998 is about 1183.1894462003.

The spelling of 1656390998 in words is "one billion, six hundred fifty-six million, three hundred ninety thousand, nine hundred ninety-eight".