68721923 has 2 divisors, whose sum is σ = 68721924. Its totient is φ = 68721922.

The previous prime is 68721847. The next prime is 68721931. The reversal of 68721923 is 32912786.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-68721923 is a prime.

It is not a weakly prime, because it can be changed into another prime (68723923) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34360961 + 34360962.

It is an arithmetic number, because the mean of its divisors is an integer number (34360962).

Almost surely, 2^68721923 is an apocalyptic number.

68721923 is a deficient number, since it is larger than the sum of its proper divisors (1).

68721923 is an equidigital number, since it uses as much as digits as its factorization.

68721923 is an evil number, because the sum of its binary digits is even.

The product of its digits is 36288, while the sum is 38.

The square root of 68721923 is about 8289.8686961857. The cubic root of 68721923 is about 409.6048602322.

The spelling of 68721923 in words is "sixty-eight million, seven hundred twenty-one thousand, nine hundred twenty-three".