74771621 has 2 divisors, whose sum is σ = 74771622. Its totient is φ = 74771620.

The previous prime is 74771617. The next prime is 74771623. The reversal of 74771621 is 12617747.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 73530625 + 1240996 = 8575^2 + 1114^2 .

It is an emirp because it is prime and its reverse (12617747) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 74771621 - 2² = 74771617 is a prime.

Together with 74771623, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (74771623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 37385810 + 37385811.

It is an arithmetic number, because the mean of its divisors is an integer number (37385811).

Almost surely, 2^74771621 is an apocalyptic number.

It is an amenable number.

74771621 is a deficient number, since it is larger than the sum of its proper divisors (1).

74771621 is an equidigital number, since it uses as much as digits as its factorization.

74771621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 16464, while the sum is 35.

The square root of 74771621 is about 8647.0585172069. The cubic root of 74771621 is about 421.2878478616.

The spelling of 74771621 in words is "seventy-four million, seven hundred seventy-one thousand, six hundred twenty-one".