71890906 has 4 divisors (see below), whose sum is σ = 107836362. Its totient is φ = 35945452.

The previous prime is 71890877. The next prime is 71890937. The reversal of 71890906 is 60909817.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 60909817 = 1279 ⋅47623.

It can be written as a sum of positive squares in only one way, i.e., 54626881 + 17264025 = 7391^2 + 4155^2 .

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 17972725 + ... + 17972728.

Almost surely, 2^71890906 is an apocalyptic number.

71890906 is a deficient number, since it is larger than the sum of its proper divisors (35945456).

71890906 is a wasteful number, since it uses less digits than its factorization.

71890906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35945455.

The product of its (nonzero) digits is 27216, while the sum is 40.

The square root of 71890906 is about 8478.8505117144. The cubic root of 71890906 is about 415.8065429689.

The spelling of 71890906 in words is "seventy-one million, eight hundred ninety thousand, nine hundred six".