72131797 has 2 divisors, whose sum is σ = 72131798. Its totient is φ = 72131796.

The previous prime is 72131791. The next prime is 72131821. The reversal of 72131797 is 79713127.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 66438801 + 5692996 = 8151^2 + 2386^2 .

It is a cyclic number.

It is not a de Polignac number, because 72131797 - 2¹¹ = 72129749 is a prime.

It is a super-2 number, since 2×72131797² = 10405992276898418, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72131791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36065898 + 36065899.

It is an arithmetic number, because the mean of its divisors is an integer number (36065899).

Almost surely, 2^72131797 is an apocalyptic number.

It is an amenable number.

72131797 is a deficient number, since it is larger than the sum of its proper divisors (1).

72131797 is an equidigital number, since it uses as much as digits as its factorization.

72131797 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18522, while the sum is 37.

The square root of 72131797 is about 8493.0440361510. The cubic root of 72131797 is about 416.2704513695.

The spelling of 72131797 in words is "seventy-two million, one hundred thirty-one thousand, seven hundred ninety-seven".