113640721 has 2 divisors, whose sum is σ = 113640722. Its totient is φ = 113640720.

The previous prime is 113640713. The next prime is 113640731. The reversal of 113640721 is 127046311.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 108910096 + 4730625 = 10436^2 + 2175^2 .

It is a cyclic number.

It is not a de Polignac number, because 113640721 - 2³ = 113640713 is a prime.

It is not a weakly prime, because it can be changed into another prime (113640731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 56820360 + 56820361.

It is an arithmetic number, because the mean of its divisors is an integer number (56820361).

Almost surely, 2^113640721 is an apocalyptic number.

It is an amenable number.

113640721 is a deficient number, since it is larger than the sum of its proper divisors (1).

113640721 is an equidigital number, since it uses as much as digits as its factorization.

113640721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1008, while the sum is 25.

The square root of 113640721 is about 10660.2401942921. The cubic root of 113640721 is about 484.3708439519.

The spelling of 113640721 in words is "one hundred thirteen million, six hundred forty thousand, seven hundred twenty-one".