71664842 has 4 divisors (see below), whose sum is σ = 107497266. Its totient is φ = 35832420.

The previous prime is 71664821. The next prime is 71664907. The reversal of 71664842 is 24846617.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 24846617 = 191 ⋅130087.

It can be written as a sum of positive squares in only one way, i.e., 36012001 + 35652841 = 6001^2 + 5971^2 .

It is a junction number, because it is equal to n+sod(n) for n = 71664796 and 71664805.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 17916209 + ... + 17916212.

Almost surely, 2^71664842 is an apocalyptic number.

71664842 is a deficient number, since it is larger than the sum of its proper divisors (35832424).

71664842 is a wasteful number, since it uses less digits than its factorization.

71664842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35832423.

The product of its digits is 64512, while the sum is 38.

The square root of 71664842 is about 8465.5089628445. The cubic root of 71664842 is about 415.3702448987.

The spelling of 71664842 in words is "seventy-one million, six hundred sixty-four thousand, eight hundred forty-two".