72791621 has 4 divisors (see below), whose sum is σ = 83190432. Its totient is φ = 62392812.

The previous prime is 72791611. The next prime is 72791623. The reversal of 72791621 is 12619727.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 72791621 - 2⁶ = 72791557 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72791623) 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 in 3 ways as a sum of consecutive naturals, for example, 5199395 + ... + 5199408.

It is an arithmetic number, because the mean of its divisors is an integer number (20797608).

Almost surely, 2^72791621 is an apocalyptic number.

It is an amenable number.

72791621 is a deficient number, since it is larger than the sum of its proper divisors (10398811).

72791621 is a wasteful number, since it uses less digits than its factorization.

72791621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10398810.

The product of its digits is 10584, while the sum is 35.

The square root of 72791621 is about 8531.8005719778. The cubic root of 72791621 is about 417.5358755790.

The spelling of 72791621 in words is "seventy-two million, seven hundred ninety-one thousand, six hundred twenty-one".