68249891 has 2 divisors, whose sum is σ = 68249892. Its totient is φ = 68249890.

The previous prime is 68249887. The next prime is 68249899. The reversal of 68249891 is 19894286.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 68249891 - 2² = 68249887 is a prime.

It is not a weakly prime, because it can be changed into another prime (68249899) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34124945 + 34124946.

It is an arithmetic number, because the mean of its divisors is an integer number (34124946).

Almost surely, 2^68249891 is an apocalyptic number.

68249891 is a deficient number, since it is larger than the sum of its proper divisors (1).

68249891 is an equidigital number, since it uses as much as digits as its factorization.

68249891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 248832, while the sum is 47.

The square root of 68249891 is about 8261.3492239464. The cubic root of 68249891 is about 408.6648837225.

The spelling of 68249891 in words is "sixty-eight million, two hundred forty-nine thousand, eight hundred ninety-one".