19972971 has 24 divisors (see below), whose sum is σ = 30551040. Its totient is φ = 12538800.

The previous prime is 19972963. The next prime is 19972987. The reversal of 19972971 is 17927991.

It is not a de Polignac number, because 19972971 - 2³ = 19972963 is a prime.

It is not an unprimeable number, because it can be changed into a prime (19972951) 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, 46126 + ... + 46556.

It is an arithmetic number, because the mean of its divisors is an integer number (1272960).

Almost surely, 2^19972971 is an apocalyptic number.

19972971 is a deficient number, since it is larger than the sum of its proper divisors (10578069).

19972971 is a wasteful number, since it uses less digits than its factorization.

19972971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 727 (or 724 counting only the distinct ones).

The product of its digits is 71442, while the sum is 45.

The square root of 19972971 is about 4469.1129992427. The cubic root of 19972971 is about 271.3194265434.

The spelling of 19972971 in words is "nineteen million, nine hundred seventy-two thousand, nine hundred seventy-one".