74640 has 40 divisors (see below), whose sum is σ = 232128. Its totient is φ = 19840.

The previous prime is 74623. The next prime is 74653. The reversal of 74640 is 4647.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×74640² = 11142259200, which contains 22 as substring.

It is a Smith number, since the sum of its digits (21) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 85 + ... + 395.

2⁷⁴⁶⁴⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 74640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (116064).

74640 is an abundant number, since it is smaller than the sum of its proper divisors (157488).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

74640 is a wasteful number, since it uses less digits than its factorization.

74640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 327 (or 321 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 21.

The square root of 74640 is about 273.2032210645. The cubic root of 74640 is about 42.1040504037.

The spelling of 74640 in words is "seventy-four thousand, six hundred forty".