72561855 has 64 divisors (see below), whose sum is σ = 129761280. Its totient is φ = 34473600.

The previous prime is 72561833. The next prime is 72561877. The reversal of 72561855 is 55816527.

It is an interprime number because it is at equal distance from previous prime (72561833) and next prime (72561877).

It is not a de Polignac number, because 72561855 - 2¹⁴ = 72545471 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 379810 + ... + 380000.

It is an arithmetic number, because the mean of its divisors is an integer number (2027520).

Almost surely, 2^72561855 is an apocalyptic number.

72561855 is a deficient number, since it is larger than the sum of its proper divisors (57199425).

72561855 is a wasteful number, since it uses less digits than its factorization.

72561855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 292.

The product of its digits is 84000, while the sum is 39.

The square root of 72561855 is about 8518.3246592273. The cubic root of 72561855 is about 417.0960966415.

The spelling of 72561855 in words is "seventy-two million, five hundred sixty-one thousand, eight hundred fifty-five".