72632821 has 4 divisors (see below), whose sum is σ = 72934444. Its totient is φ = 72331200.

The previous prime is 72632803. The next prime is 72632831. The reversal of 72632821 is 12823627.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 62583921 + 10048900 = 7911^2 + 3170^2 .

It is a cyclic number.

It is not a de Polignac number, because 72632821 - 2⁹ = 72632309 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 (72632831) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 150450 + ... + 150931.

It is an arithmetic number, because the mean of its divisors is an integer number (18233611).

Almost surely, 2^72632821 is an apocalyptic number.

It is an amenable number.

72632821 is a deficient number, since it is larger than the sum of its proper divisors (301623).

72632821 is a wasteful number, since it uses less digits than its factorization.

72632821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 301622.

The product of its digits is 8064, while the sum is 31.

The square root of 72632821 is about 8522.4891317032. The cubic root of 72632821 is about 417.2320266343.

The spelling of 72632821 in words is "seventy-two million, six hundred thirty-two thousand, eight hundred twenty-one".