72765561 has 8 divisors (see below), whose sum is σ = 105840864. Its totient is φ = 44100320.

The previous prime is 72765547. The next prime is 72765577. The reversal of 72765561 is 16556727.

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

It is not a de Polignac number, because 72765561 - 2¹³ = 72757369 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (72761561) 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, 1102476 + ... + 1102541.

It is an arithmetic number, because the mean of its divisors is an integer number (13230108).

Almost surely, 2^72765561 is an apocalyptic number.

It is an amenable number.

72765561 is a deficient number, since it is larger than the sum of its proper divisors (33075303).

72765561 is a wasteful number, since it uses less digits than its factorization.

72765561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2205031.

The product of its digits is 88200, while the sum is 39.

The square root of 72765561 is about 8530.2732078170. The cubic root of 72765561 is about 417.4860425372.

The spelling of 72765561 in words is "seventy-two million, seven hundred sixty-five thousand, five hundred sixty-one".