74644561 has 2 divisors, whose sum is σ = 74644562. Its totient is φ = 74644560.

The previous prime is 74644547. The next prime is 74644571. The reversal of 74644561 is 16544647.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 40246336 + 34398225 = 6344^2 + 5865^2 .

It is a cyclic number.

It is not a de Polignac number, because 74644561 - 2¹³ = 74636369 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 74644561.

It is not a weakly prime, because it can be changed into another prime (74644571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 37322280 + 37322281.

It is an arithmetic number, because the mean of its divisors is an integer number (37322281).

Almost surely, 2^74644561 is an apocalyptic number.

It is an amenable number.

74644561 is a deficient number, since it is larger than the sum of its proper divisors (1).

74644561 is an equidigital number, since it uses as much as digits as its factorization.

74644561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 80640, while the sum is 37.

The square root of 74644561 is about 8639.7083862825. The cubic root of 74644561 is about 421.0490799862.

The spelling of 74644561 in words is "seventy-four million, six hundred forty-four thousand, five hundred sixty-one".