84806713721 has 2 divisors, whose sum is σ = 84806713722. Its totient is φ = 84806713720.

The previous prime is 84806713703. The next prime is 84806713727. The reversal of 84806713721 is 12731760848.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 84427438096 + 379275625 = 290564^2 + 19475^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-84806713721 is a prime.

It is not a weakly prime, because it can be changed into another prime (84806713727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42403356860 + 42403356861.

It is an arithmetic number, because the mean of its divisors is an integer number (42403356861).

Almost surely, 2^84806713721 is an apocalyptic number.

It is an amenable number.

84806713721 is a deficient number, since it is larger than the sum of its proper divisors (1).

84806713721 is an equidigital number, since it uses as much as digits as its factorization.

84806713721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 451584, while the sum is 47.

The spelling of 84806713721 in words is "eighty-four billion, eight hundred six million, seven hundred thirteen thousand, seven hundred twenty-one".