72583781 has 8 divisors (see below), whose sum is σ = 79039200. Its totient is φ = 66391920.

The previous prime is 72583759. The next prime is 72583801. The reversal of 72583781 is 18738527.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72583781 is a prime.

It is a super-2 number, since 2×72583781² = 10536810528511922, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72583481) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 65315 + ... + 66416.

It is an arithmetic number, because the mean of its divisors is an integer number (9879900).

Almost surely, 2^72583781 is an apocalyptic number.

It is an amenable number.

72583781 is a deficient number, since it is larger than the sum of its proper divisors (6455419).

72583781 is a wasteful number, since it uses less digits than its factorization.

72583781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131779.

The product of its digits is 94080, while the sum is 41.

The square root of 72583781 is about 8519.6115521777. The cubic root of 72583781 is about 417.1381036897.

The spelling of 72583781 in words is "seventy-two million, five hundred eighty-three thousand, seven hundred eighty-one".