71839690 has 32 divisors (see below), whose sum is σ = 139897296. Its totient is φ = 26403840.

The previous prime is 71839657. The next prime is 71839697. The reversal of 71839690 is 9693817.

It can be written as a sum of positive squares in 8 ways, for example, as 19175641 + 52664049 = 4379^2 + 7257^2 .

It is a super-2 number, since 2×71839690² = 10321882118592200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (71839697) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 30184 + ... + 32476.

Almost surely, 2^71839690 is an apocalyptic number.

71839690 is a deficient number, since it is larger than the sum of its proper divisors (68057606).

71839690 is a wasteful number, since it uses less digits than its factorization.

71839690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2554.

The product of its (nonzero) digits is 81648, while the sum is 43.

The square root of 71839690 is about 8475.8297528915. The cubic root of 71839690 is about 415.7077775466.

The spelling of 71839690 in words is "seventy-one million, eight hundred thirty-nine thousand, six hundred ninety".