72638969 has 4 divisors (see below), whose sum is σ = 78226596. Its totient is φ = 67051344.

The previous prime is 72638959. The next prime is 72638981. The reversal of 72638969 is 96983627.

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 48511225 + 24127744 = 6965^2 + 4912^2 .

It is a cyclic number.

It is not a de Polignac number, because 72638969 - 2⁴ = 72638953 is a prime.

It is a super-2 number, since 2×72638969² = 10552839634765922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72638959) 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, 2793794 + ... + 2793819.

It is an arithmetic number, because the mean of its divisors is an integer number (19556649).

Almost surely, 2^72638969 is an apocalyptic number.

It is an amenable number.

72638969 is a deficient number, since it is larger than the sum of its proper divisors (5587627).

72638969 is a wasteful number, since it uses less digits than its factorization.

72638969 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5587626.

The product of its digits is 979776, while the sum is 50.

The square root of 72638969 is about 8522.8498168160. The cubic root of 72638969 is about 417.2437984939.

The spelling of 72638969 in words is "seventy-two million, six hundred thirty-eight thousand, nine hundred sixty-nine".