74521821 has 16 divisors (see below), whose sum is σ = 108733248. Its totient is φ = 45024000.

The previous prime is 74521757. The next prime is 74521823. The reversal of 74521821 is 12812547.

It is not a de Polignac number, because 74521821 - 2⁶ = 74521757 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (74521823) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7771 + ... + 14471.

It is an arithmetic number, because the mean of its divisors is an integer number (6795828).

Almost surely, 2^74521821 is an apocalyptic number.

It is an amenable number.

74521821 is a deficient number, since it is larger than the sum of its proper divisors (34211427).

74521821 is a wasteful number, since it uses less digits than its factorization.

74521821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7052.

The product of its digits is 4480, while the sum is 30.

The square root of 74521821 is about 8632.6022148597. The cubic root of 74521821 is about 420.8181727135.

The spelling of 74521821 in words is "seventy-four million, five hundred twenty-one thousand, eight hundred twenty-one".