75981621 has 4 divisors (see below), whose sum is σ = 101308832. Its totient is φ = 50654412.

The previous prime is 75981617. The next prime is 75981623. The reversal of 75981621 is 12618957.

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.

It is not a de Polignac number, because 75981621 - 2² = 75981617 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 75981621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (75981623) 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, 12663601 + ... + 12663606.

It is an arithmetic number, because the mean of its divisors is an integer number (25327208).

Almost surely, 2^75981621 is an apocalyptic number.

It is an amenable number.

75981621 is a deficient number, since it is larger than the sum of its proper divisors (25327211).

75981621 is a wasteful number, since it uses less digits than its factorization.

75981621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25327210.

The product of its digits is 30240, while the sum is 39.

The square root of 75981621 is about 8716.7437154020. The cubic root of 75981621 is about 423.5482108474.

The spelling of 75981621 in words is "seventy-five million, nine hundred eighty-one thousand, six hundred twenty-one".