19972939 has 12 divisors (see below), whose sum is σ = 23565168. Its totient is φ = 16875600.

The previous prime is 19972913. The next prime is 19972949. The reversal of 19972939 is 93927991.

It is a de Polignac number, because none of the positive numbers 2^k-19972939 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (49).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 19972892 and 19972901.

It is not an unprimeable number, because it can be changed into a prime (19972949) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 609 + ... + 6349.

It is an arithmetic number, because the mean of its divisors is an integer number (1963764).

Almost surely, 2^19972939 is an apocalyptic number.

19972939 is a deficient number, since it is larger than the sum of its proper divisors (3592229).

19972939 is an equidigital number, since it uses as much as digits as its factorization.

19972939 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5826 (or 5819 counting only the distinct ones).

The product of its digits is 275562, while the sum is 49.

The square root of 19972939 is about 4469.1094191125. The cubic root of 19972939 is about 271.3192816438.

The spelling of 19972939 in words is "nineteen million, nine hundred seventy-two thousand, nine hundred thirty-nine".