77044421 has 4 divisors (see below), whose sum is σ = 78683712. Its totient is φ = 75405132.

The previous prime is 77044381. The next prime is 77044441. The reversal of 77044421 is 12444077.

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 a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77044421 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77044441) 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, 819575 + ... + 819668.

It is an arithmetic number, because the mean of its divisors is an integer number (19670928).

Almost surely, 2^77044421 is an apocalyptic number.

It is an amenable number.

77044421 is a deficient number, since it is larger than the sum of its proper divisors (1639291).

77044421 is a wasteful number, since it uses less digits than its factorization.

77044421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1639290.

The product of its (nonzero) digits is 6272, while the sum is 29.

The square root of 77044421 is about 8777.4951438323. The cubic root of 77044421 is about 425.5138808223.

Adding to 77044421 its reverse (12444077), we get a palindrome (89488498).

The spelling of 77044421 in words is "seventy-seven million, forty-four thousand, four hundred twenty-one".