19997400 has 48 divisors (see below), whose sum is σ = 61993800. Its totient is φ = 5332480.

The previous prime is 19997399. The next prime is 19997413. The reversal of 19997400 is 479991.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16065 + ... + 17264.

Almost surely, 2^19997400 is an apocalyptic number.

19997400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19997400 is an abundant number, since it is smaller than the sum of its proper divisors (41996400).

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

19997400 is a wasteful number, since it uses less digits than its factorization.

19997400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33348 (or 33339 counting only the distinct ones).

The product of its (nonzero) digits is 20412, while the sum is 39.

The square root of 19997400 is about 4471.8452567145. The cubic root of 19997400 is about 271.4299986734.

The spelling of 19997400 in words is "nineteen million, nine hundred ninety-seven thousand, four hundred".