72155653561 has 8 divisors (see below), whose sum is σ = 73445954400. Its totient is φ = 70867596960.

The previous prime is 72155653501. The next prime is 72155653589. The reversal of 72155653561 is 16535655127.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 72155653561 - 2⁷ = 72155653433 is a prime.

It is a super-3 number, since 3×72155653561³ (a number of 34 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72155653501) 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, 496116 + ... + 624853.

It is an arithmetic number, because the mean of its divisors is an integer number (9180744300).

Almost surely, 2^72155653561 is an apocalyptic number.

It is an amenable number.

72155653561 is a deficient number, since it is larger than the sum of its proper divisors (1290300839).

72155653561 is a wasteful number, since it uses less digits than its factorization.

72155653561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1122119.

The product of its digits is 945000, while the sum is 46.

The spelling of 72155653561 in words is "seventy-two billion, one hundred fifty-five million, six hundred fifty-three thousand, five hundred sixty-one".