74478781 has 4 divisors (see below), whose sum is σ = 80207932. Its totient is φ = 68749632.

The previous prime is 74478779. The next prime is 74478791. The reversal of 74478781 is 18787447.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2924100 + 71554681 = 1710^2 + 8459^2 .

It is a cyclic number.

It is not a de Polignac number, because 74478781 - 2¹ = 74478779 is a prime.

It is a super-2 number, since 2×74478781² = 11094177638491922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (74478791) 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, 2864556 + ... + 2864581.

It is an arithmetic number, because the mean of its divisors is an integer number (20051983).

Almost surely, 2^74478781 is an apocalyptic number.

It is an amenable number.

74478781 is a deficient number, since it is larger than the sum of its proper divisors (5729151).

74478781 is a wasteful number, since it uses less digits than its factorization.

74478781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5729150.

The product of its digits is 351232, while the sum is 46.

The square root of 74478781 is about 8630.1089796132. The cubic root of 74478781 is about 420.7371427464.

The spelling of 74478781 in words is "seventy-four million, four hundred seventy-eight thousand, seven hundred eighty-one".