71988965 has 24 divisors (see below), whose sum is σ = 95677848. Its totient is φ = 51814400.

The previous prime is 71988953. The next prime is 71989019. The reversal of 71988965 is 56988917.

It can be written as a sum of positive squares in 4 ways, for example, as 39715204 + 32273761 = 6302^2 + 5681^2 .

It is not a de Polignac number, because 71988965 - 2⁶ = 71988901 is a prime.

It is a super-2 number, since 2×71988965² = 10364822163542450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 44165 + ... + 45765.

It is an arithmetic number, because the mean of its divisors is an integer number (3986577).

Almost surely, 2^71988965 is an apocalyptic number.

It is an amenable number.

71988965 is a deficient number, since it is larger than the sum of its proper divisors (23688883).

71988965 is a wasteful number, since it uses less digits than its factorization.

71988965 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1669 (or 1646 counting only the distinct ones).

The product of its digits is 1088640, while the sum is 53.

The square root of 71988965 is about 8484.6311057111. The cubic root of 71988965 is about 415.9955100754.

The spelling of 71988965 in words is "seventy-one million, nine hundred eighty-eight thousand, nine hundred sixty-five".