65981751 has 16 divisors (see below), whose sum is σ = 98316288. Its totient is φ = 39012800.

The previous prime is 65981731. The next prime is 65981759. The reversal of 65981751 is 15718956.

It is a cyclic number.

It is not a de Polignac number, because 65981751 - 2¹⁰ = 65980727 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65981759) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23031 + ... + 25736.

It is an arithmetic number, because the mean of its divisors is an integer number (6144768).

Almost surely, 2^65981751 is an apocalyptic number.

65981751 is a deficient number, since it is larger than the sum of its proper divisors (32334537).

65981751 is a wasteful number, since it uses less digits than its factorization.

65981751 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48822.

The product of its digits is 75600, while the sum is 42.

The square root of 65981751 is about 8122.9151786782. The cubic root of 65981751 is about 404.0867518666.

The spelling of 65981751 in words is "sixty-five million, nine hundred eighty-one thousand, seven hundred fifty-one".