99971964 has 18 divisors (see below), whose sum is σ = 252707000. Its totient is φ = 33323976.

The previous prime is 99971953. The next prime is 99972013. The reversal of 99971964 is 46917999.

It is a tau number, because it is divible by the number of its divisors (18).

It is a hoax number, since the sum of its digits (54) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 99971964.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1388464 + ... + 1388535.

Almost surely, 2^99971964 is an apocalyptic number.

It is an amenable number.

99971964 is an abundant number, since it is smaller than the sum of its proper divisors (152735036).

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

99971964 is a wasteful number, since it uses less digits than its factorization.

99971964 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2777009 (or 2777004 counting only the distinct ones).

The product of its digits is 1102248, while the sum is 54.

The square root of 99971964 is about 9998.5981017341. The cubic root of 99971964 is about 464.1155021121.

The spelling of 99971964 in words is "ninety-nine million, nine hundred seventy-one thousand, nine hundred sixty-four".