81351701 has 2 divisors, whose sum is σ = 81351702. Its totient is φ = 81351700.

The previous prime is 81351679. The next prime is 81351733. The reversal of 81351701 is 10715318.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 80532676 + 819025 = 8974^2 + 905^2 .

It is a cyclic number.

It is not a de Polignac number, because 81351701 - 2²² = 77157397 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81351791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40675850 + 40675851.

It is an arithmetic number, because the mean of its divisors is an integer number (40675851).

Almost surely, 2^81351701 is an apocalyptic number.

It is an amenable number.

81351701 is a deficient number, since it is larger than the sum of its proper divisors (1).

81351701 is an equidigital number, since it uses as much as digits as its factorization.

81351701 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 840, while the sum is 26.

The square root of 81351701 is about 9019.5177809016. The cubic root of 81351701 is about 433.3001899043.

The spelling of 81351701 in words is "eighty-one million, three hundred fifty-one thousand, seven hundred one".