77144921 has 16 divisors (see below), whose sum is σ = 96844800. Its totient is φ = 59917968.

The previous prime is 77144917. The next prime is 77144941. The reversal of 77144921 is 12944177.

It is a cyclic number.

It is not a de Polignac number, because 77144921 - 2² = 77144917 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77144941) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9551 + ... + 15668.

It is an arithmetic number, because the mean of its divisors is an integer number (6052800).

Almost surely, 2^77144921 is an apocalyptic number.

It is an amenable number.

77144921 is a deficient number, since it is larger than the sum of its proper divisors (19699879).

77144921 is a wasteful number, since it uses less digits than its factorization.

77144921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25268.

The product of its digits is 14112, while the sum is 35.

The square root of 77144921 is about 8783.2181459873. The cubic root of 77144921 is about 425.6988198634.

The spelling of 77144921 in words is "seventy-seven million, one hundred forty-four thousand, nine hundred twenty-one".