72521677 has 4 divisors (see below), whose sum is σ = 76787676. Its totient is φ = 68255680.

The previous prime is 72521653. The next prime is 72521707. The reversal of 72521677 is 77612527.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 77612527 = 6329 ⋅12263.

It can be written as a sum of positive squares in 2 ways, for example, as 49154121 + 23367556 = 7011^2 + 4834^2 .

It is not a de Polignac number, because 72521677 - 2⁷ = 72521549 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72521627) 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, 2132974 + ... + 2133007.

It is an arithmetic number, because the mean of its divisors is an integer number (19196919).

Almost surely, 2^72521677 is an apocalyptic number.

It is an amenable number.

72521677 is a deficient number, since it is larger than the sum of its proper divisors (4265999).

72521677 is a wasteful number, since it uses less digits than its factorization.

72521677 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4265998.

The product of its digits is 41160, while the sum is 37.

The square root of 72521677 is about 8515.9660050989. The cubic root of 72521677 is about 417.0190994325.

The spelling of 72521677 in words is "seventy-two million, five hundred twenty-one thousand, six hundred seventy-seven".