72668681 has 4 divisors (see below), whose sum is σ = 75012864. Its totient is φ = 70324500.

The previous prime is 72668657. The next prime is 72668683. The reversal of 72668681 is 18686627.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 72668681 - 2¹⁰ = 72667657 is a prime.

It is a super-2 number, since 2×72668681² = 10561474396559522, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (72668683) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1172045 + ... + 1172106.

It is an arithmetic number, because the mean of its divisors is an integer number (18753216).

Almost surely, 2^72668681 is an apocalyptic number.

It is an amenable number.

72668681 is a deficient number, since it is larger than the sum of its proper divisors (2344183).

72668681 is a wasteful number, since it uses less digits than its factorization.

72668681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2344182.

The product of its digits is 193536, while the sum is 44.

The square root of 72668681 is about 8524.5927175438. The cubic root of 72668681 is about 417.3006800733.

The spelling of 72668681 in words is "seventy-two million, six hundred sixty-eight thousand, six hundred eighty-one".