72605251561 has 4 divisors (see below), whose sum is σ = 73480013712. Its totient is φ = 71730489412.

The previous prime is 72605251547. The next prime is 72605251583. The reversal of 72605251561 is 16515250627.

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 not a de Polignac number, because 72605251561 - 2²³ = 72596862953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72605251501) 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, 437380951 + ... + 437381116.

It is an arithmetic number, because the mean of its divisors is an integer number (18370003428).

Almost surely, 2^72605251561 is an apocalyptic number.

It is an amenable number.

72605251561 is a deficient number, since it is larger than the sum of its proper divisors (874762151).

72605251561 is an equidigital number, since it uses as much as digits as its factorization.

72605251561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 874762150.

The product of its (nonzero) digits is 126000, while the sum is 40.

The spelling of 72605251561 in words is "seventy-two billion, six hundred five million, two hundred fifty-one thousand, five hundred sixty-one".