19682991 has 24 divisors (see below), whose sum is σ = 30420000. Its totient is φ = 12220416.

The previous prime is 19682987. The next prime is 19683007. The reversal of 19682991 is 19928691.

It is not a de Polignac number, because 19682991 - 2² = 19682987 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19682921) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 15135 + ... + 16383.

It is an arithmetic number, because the mean of its divisors is an integer number (1267500).

Almost surely, 2^19682991 is an apocalyptic number.

19682991 is a deficient number, since it is larger than the sum of its proper divisors (10737009).

19682991 is a wasteful number, since it uses less digits than its factorization.

19682991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1375 (or 1372 counting only the distinct ones).

The product of its digits is 69984, while the sum is 45.

The square root of 19682991 is about 4436.5517014907. The cubic root of 19682991 is about 269.9999588477. Note that the first 4 decimals are identical.

The spelling of 19682991 in words is "nineteen million, six hundred eighty-two thousand, nine hundred ninety-one".