68511151 has 4 divisors (see below), whose sum is σ = 68591952. Its totient is φ = 68430352.

The previous prime is 68511133. The next prime is 68511199. The reversal of 68511151 is 15111586.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-68511151 is a prime.

It is a super-2 number, since 2×68511151² = 9387555622689602, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68514151) 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, 39115 + ... + 40828.

It is an arithmetic number, because the mean of its divisors is an integer number (17147988).

Almost surely, 2^68511151 is an apocalyptic number.

68511151 is a deficient number, since it is larger than the sum of its proper divisors (80801).

68511151 is an equidigital number, since it uses as much as digits as its factorization.

68511151 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80800.

The product of its digits is 1200, while the sum is 28.

The square root of 68511151 is about 8277.1463077561. The cubic root of 68511151 is about 409.1856749871.

The spelling of 68511151 in words is "sixty-eight million, five hundred eleven thousand, one hundred fifty-one".