19900656 has 60 divisors (see below), whose sum is σ = 56233008. Its totient is φ = 6569472.

The previous prime is 19900651. The next prime is 19900663. The reversal of 19900656 is 65600991.

It is a super-2 number, since 2×19900656² = 792072218460672, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 19900656.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19900651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15661 + ... + 16883.

Almost surely, 2^19900656 is an apocalyptic number.

19900656 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19900656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28116504).

19900656 is an abundant number, since it is smaller than the sum of its proper divisors (36332352).

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

19900656 is a wasteful number, since it uses less digits than its factorization.

19900656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1350 (or 1341 counting only the distinct ones).

The product of its (nonzero) digits is 14580, while the sum is 36.

The square root of 19900656 is about 4461.0151311109. The cubic root of 19900656 is about 270.9915802815.

The spelling of 19900656 in words is "nineteen million, nine hundred thousand, six hundred fifty-six".