19976640 has 56 divisors (see below), whose sum is σ = 63428880. Its totient is φ = 5326848.

The previous prime is 19976629. The next prime is 19976641. The reversal of 19976640 is 4667991.

It is a super-2 number, since 2×19976640² = 798132291379200, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 19976592 and 19976601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19976641) 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, 9445 + ... + 11364.

Almost surely, 2^19976640 is an apocalyptic number.

19976640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19976640 is an abundant number, since it is smaller than the sum of its proper divisors (43452240).

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

19976640 is a wasteful number, since it uses less digits than its factorization.

19976640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20829 (or 20819 counting only the distinct ones).

The product of its (nonzero) digits is 81648, while the sum is 42.

The square root of 19976640 is about 4469.5234645318. The cubic root of 19976640 is about 271.3360391616.

The spelling of 19976640 in words is "nineteen million, nine hundred seventy-six thousand, six hundred forty".