84936721 has 2 divisors, whose sum is σ = 84936722. Its totient is φ = 84936720.

The previous prime is 84936713. The next prime is 84936727. The reversal of 84936721 is 12763948.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 79923600 + 5013121 = 8940^2 + 2239^2 .

It is a cyclic number.

It is not a de Polignac number, because 84936721 - 2³ = 84936713 is a prime.

It is not a weakly prime, because it can be changed into another prime (84936727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42468360 + 42468361.

It is an arithmetic number, because the mean of its divisors is an integer number (42468361).

Almost surely, 2^84936721 is an apocalyptic number.

It is an amenable number.

84936721 is a deficient number, since it is larger than the sum of its proper divisors (1).

84936721 is an equidigital number, since it uses as much as digits as its factorization.

84936721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 72576, while the sum is 40.

The square root of 84936721 is about 9216.1120327392. The cubic root of 84936721 is about 439.5738315075.

The spelling of 84936721 in words is "eighty-four million, nine hundred thirty-six thousand, seven hundred twenty-one".