74560721 has 4 divisors (see below), whose sum is σ = 75610944. Its totient is φ = 73510500.

The previous prime is 74560697. The next prime is 74560747. The reversal of 74560721 is 12706547.

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: 12706547 = 7 ⋅1815221.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-74560721 is a prime.

It is a super-2 number, since 2×74560721² = 11118602232079682, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (74560621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 525005 + ... + 525146.

It is an arithmetic number, because the mean of its divisors is an integer number (18902736).

Almost surely, 2^74560721 is an apocalyptic number.

74560721 is a gapful number since it is divisible by the number (71) formed by its first and last digit.

It is an amenable number.

74560721 is a deficient number, since it is larger than the sum of its proper divisors (1050223).

74560721 is a wasteful number, since it uses less digits than its factorization.

74560721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1050222.

The product of its (nonzero) digits is 11760, while the sum is 32.

The square root of 74560721 is about 8634.8550074683. The cubic root of 74560721 is about 420.8913816037.

The spelling of 74560721 in words is "seventy-four million, five hundred sixty thousand, seven hundred twenty-one".