72961009 has 4 divisors (see below), whose sum is σ = 79593840. Its totient is φ = 66328180.

The previous prime is 72961001. The next prime is 72961039. The reversal of 72961009 is 90016927.

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 72961009 - 2³ = 72961001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72961001) 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, 3316399 + ... + 3316420.

It is an arithmetic number, because the mean of its divisors is an integer number (19898460).

Almost surely, 2^72961009 is an apocalyptic number.

It is an amenable number.

72961009 is a deficient number, since it is larger than the sum of its proper divisors (6632831).

72961009 is a wasteful number, since it uses less digits than its factorization.

72961009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6632830.

The product of its (nonzero) digits is 6804, while the sum is 34.

The square root of 72961009 is about 8541.7216648636. The cubic root of 72961009 is about 417.8594969732.

It can be divided in two parts, 729 and 61009, that multiplied together give a square (44475561 = 6669²).

The spelling of 72961009 in words is "seventy-two million, nine hundred sixty-one thousand, nine".