72869891 has 2 divisors, whose sum is σ = 72869892. Its totient is φ = 72869890.

The previous prime is 72869873. The next prime is 72869893. The reversal of 72869891 is 19896827.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 72869891 - 2¹⁰ = 72868867 is a prime.

Together with 72869893, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (72869893) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36434945 + 36434946.

It is an arithmetic number, because the mean of its divisors is an integer number (36434946).

Almost surely, 2^72869891 is an apocalyptic number.

72869891 is a deficient number, since it is larger than the sum of its proper divisors (1).

72869891 is an equidigital number, since it uses as much as digits as its factorization.

72869891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 435456, while the sum is 50.

The square root of 72869891 is about 8536.3862963200. The cubic root of 72869891 is about 417.6854753367.

The spelling of 72869891 in words is "seventy-two million, eight hundred sixty-nine thousand, eight hundred ninety-one".