74386721 has 8 divisors (see below), whose sum is σ = 75302784. Its totient is φ = 73474960.

The previous prime is 74386717. The next prime is 74386727. The reversal of 74386721 is 12768347.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 74386721 - 2² = 74386717 is a prime.

It is a super-2 number, since 2×74386721² = 11066768522263682, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (74386727) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 45311 + ... + 46923.

It is an arithmetic number, because the mean of its divisors is an integer number (9412848).

Almost surely, 2^74386721 is an apocalyptic number.

It is an amenable number.

74386721 is a deficient number, since it is larger than the sum of its proper divisors (916063).

74386721 is a wasteful number, since it uses less digits than its factorization.

74386721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2151.

The product of its digits is 56448, while the sum is 38.

The square root of 74386721 is about 8624.7736781901. The cubic root of 74386721 is about 420.5637196113.

The spelling of 74386721 in words is "seventy-four million, three hundred eighty-six thousand, seven hundred twenty-one".