71921013 has 16 divisors (see below), whose sum is σ = 98404416. Its totient is φ = 46707840.

The previous prime is 71920993. The next prime is 71921039. The reversal of 71921013 is 31012917.

It is not a de Polignac number, because 71921013 - 2⁹ = 71920501 is a prime.

It is a super-2 number, since 2×71921013² = 10345264221892338, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71921063) 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, 17745 + ... + 21417.

It is an arithmetic number, because the mean of its divisors is an integer number (6150276).

Almost surely, 2^71921013 is an apocalyptic number.

It is an amenable number.

71921013 is a deficient number, since it is larger than the sum of its proper divisors (26483403).

71921013 is a wasteful number, since it uses less digits than its factorization.

71921013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3844.

The product of its (nonzero) digits is 378, while the sum is 24.

The square root of 71921013 is about 8480.6257434225. The cubic root of 71921013 is about 415.8645797041.

The spelling of 71921013 in words is "seventy-one million, nine hundred twenty-one thousand, thirteen".