74181921 has 16 divisors (see below), whose sum is σ = 108622848. Its totient is φ = 44658000.

The previous prime is 74181907. The next prime is 74181949. The reversal of 74181921 is 12918147.

It is not a de Polignac number, because 74181921 - 2¹¹ = 74179873 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (74181521) 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, 2461 + ... + 12426.

It is an arithmetic number, because the mean of its divisors is an integer number (6788928).

Almost surely, 2^74181921 is an apocalyptic number.

It is an amenable number.

74181921 is a deficient number, since it is larger than the sum of its proper divisors (34440927).

74181921 is a wasteful number, since it uses less digits than its factorization.

74181921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15052.

The product of its digits is 4032, while the sum is 33.

The square root of 74181921 is about 8612.8927196384. The cubic root of 74181921 is about 420.1774023813.

It can be divided in two parts, 7418 and 1921, that added together give a palindrome (9339).

The spelling of 74181921 in words is "seventy-four million, one hundred eighty-one thousand, nine hundred twenty-one".