68907791 has 4 divisors (see below), whose sum is σ = 70207992. Its totient is φ = 67607592.

The previous prime is 68907779. The next prime is 68907821. The reversal of 68907791 is 19770986.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19770986 = 2 ⋅9885493.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-68907791 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68907731) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 650021 + ... + 650126.

It is an arithmetic number, because the mean of its divisors is an integer number (17551998).

Almost surely, 2^68907791 is an apocalyptic number.

68907791 is a deficient number, since it is larger than the sum of its proper divisors (1300201).

68907791 is a wasteful number, since it uses less digits than its factorization.

68907791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1300200.

The product of its (nonzero) digits is 190512, while the sum is 47.

The square root of 68907791 is about 8301.0716778016. The cubic root of 68907791 is about 409.9738055841.

The spelling of 68907791 in words is "sixty-eight million, nine hundred seven thousand, seven hundred ninety-one".