73931381 has 4 divisors (see below), whose sum is σ = 74194764. Its totient is φ = 73668000.

The previous prime is 73931371. The next prime is 73931393. The reversal of 73931381 is 18313937.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18313937 = 1669 ⋅10973.

It can be written as a sum of positive squares in 2 ways, for example, as 55741156 + 18190225 = 7466^2 + 4265^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-73931381 is a prime.

It is a super-2 number, since 2×73931381² = 10931698193134322, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (73931371) 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, 131270 + ... + 131831.

It is an arithmetic number, because the mean of its divisors is an integer number (18548691).

Almost surely, 2^73931381 is an apocalyptic number.

It is an amenable number.

73931381 is a deficient number, since it is larger than the sum of its proper divisors (263383).

73931381 is a wasteful number, since it uses less digits than its factorization.

73931381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 263382.

The product of its digits is 13608, while the sum is 35.

The square root of 73931381 is about 8598.3359436579. The cubic root of 73931381 is about 419.7038369391.

The spelling of 73931381 in words is "seventy-three million, nine hundred thirty-one thousand, three hundred eighty-one".