74509621 has 4 divisors (see below), whose sum is σ = 78431200. Its totient is φ = 70588044.

The previous prime is 74509579. The next prime is 74509639. The reversal of 74509621 is 12690547.

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, and also an emirpimes, since its reverse is a distinct semiprime: 12690547 = 43 ⋅295129.

It is a cyclic number.

It is not a de Polignac number, because 74509621 - 2⁷ = 74509493 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 (74509651) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1960761 + ... + 1960798.

It is an arithmetic number, because the mean of its divisors is an integer number (19607800).

Almost surely, 2^74509621 is an apocalyptic number.

It is an amenable number.

74509621 is a deficient number, since it is larger than the sum of its proper divisors (3921579).

74509621 is a wasteful number, since it uses less digits than its factorization.

74509621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3921578.

The product of its (nonzero) digits is 15120, while the sum is 34.

The square root of 74509621 is about 8631.8955623895. The cubic root of 74509621 is about 420.7952073511.

It can be divided in two parts, 7450 and 9621, that added together give a palindrome (17071).

The spelling of 74509621 in words is "seventy-four million, five hundred nine thousand, six hundred twenty-one".