77221643 has 8 divisors (see below), whose sum is σ = 81441600. Its totient is φ = 73017288.

The previous prime is 77221637. The next prime is 77221673. The reversal of 77221643 is 34612277.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 77221643 - 2²⁰ = 76173067 is a prime.

It is not an unprimeable number, because it can be changed into a prime (77221673) 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 7 ways as a sum of consecutive naturals, for example, 7088 + ... + 14306.

It is an arithmetic number, because the mean of its divisors is an integer number (10180200).

Almost surely, 2^77221643 is an apocalyptic number.

77221643 is a deficient number, since it is larger than the sum of its proper divisors (4219957).

77221643 is a wasteful number, since it uses less digits than its factorization.

77221643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7801.

The product of its digits is 14112, while the sum is 32.

The square root of 77221643 is about 8787.5845941874. The cubic root of 77221643 is about 425.8398947965.

The spelling of 77221643 in words is "seventy-seven million, two hundred twenty-one thousand, six hundred forty-three".