72949891 has 4 divisors (see below), whose sum is σ = 83371312. Its totient is φ = 62528472.

The previous prime is 72949879. The next prime is 72949909. The reversal of 72949891 is 19894927.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 72949891 - 2⁷ = 72949763 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72949861) 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, 5210700 + ... + 5210713.

It is an arithmetic number, because the mean of its divisors is an integer number (20842828).

Almost surely, 2^72949891 is an apocalyptic number.

72949891 is a deficient number, since it is larger than the sum of its proper divisors (10421421).

72949891 is a wasteful number, since it uses less digits than its factorization.

72949891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10421420.

The product of its digits is 326592, while the sum is 49.

The square root of 72949891 is about 8541.0708345031. The cubic root of 72949891 is about 417.8382710337.

The spelling of 72949891 in words is "seventy-two million, nine hundred forty-nine thousand, eight hundred ninety-one".