71989631 has 4 divisors (see below), whose sum is σ = 82273872. Its totient is φ = 61705392.

The previous prime is 71989601. The next prime is 71989633. The reversal of 71989631 is 13698917.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13698917 = 37 ⋅370241.

It is not a de Polignac number, because 71989631 - 2¹⁴ = 71973247 is a prime.

It is a super-2 number, since 2×71989631² = 10365013943032322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71989633) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5142110 + ... + 5142123.

It is an arithmetic number, because the mean of its divisors is an integer number (20568468).

Almost surely, 2^71989631 is an apocalyptic number.

71989631 is a deficient number, since it is larger than the sum of its proper divisors (10284241).

71989631 is a wasteful number, since it uses less digits than its factorization.

71989631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10284240.

The product of its digits is 81648, while the sum is 44.

The square root of 71989631 is about 8484.6703530544. The cubic root of 71989631 is about 415.9967929209.

The spelling of 71989631 in words is "seventy-one million, nine hundred eighty-nine thousand, six hundred thirty-one".