72897431 has 2 divisors, whose sum is σ = 72897432. Its totient is φ = 72897430.

The previous prime is 72897421. The next prime is 72897491. The reversal of 72897431 is 13479827.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 72897431 - 2⁶ = 72897367 is a prime.

It is a super-2 number, since 2×72897431² = 10628070892799522, which contains 22 as substring.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72897401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36448715 + 36448716.

It is an arithmetic number, because the mean of its divisors is an integer number (36448716).

Almost surely, 2^72897431 is an apocalyptic number.

72897431 is a deficient number, since it is larger than the sum of its proper divisors (1).

72897431 is an equidigital number, since it uses as much as digits as its factorization.

72897431 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 84672, while the sum is 41.

The square root of 72897431 is about 8537.9992386976. Note that the first 3 decimals coincide. The cubic root of 72897431 is about 417.7380878722.

The spelling of 72897431 in words is "seventy-two million, eight hundred ninety-seven thousand, four hundred thirty-one".