65425981 has 4 divisors (see below), whose sum is σ = 65461500. Its totient is φ = 65390464.

The previous prime is 65425973. The next prime is 65425991. The reversal of 65425981 is 18952456.

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

It can be written as a sum of positive squares in 2 ways, for example, as 26163225 + 39262756 = 5115^2 + 6266^2 .

It is a cyclic number.

It is not a de Polignac number, because 65425981 - 2³ = 65425973 is a prime.

It is a super-2 number, since 2×65425981² = 8561117979624722, 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 (65425901) 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, 14836 + ... + 18733.

It is an arithmetic number, because the mean of its divisors is an integer number (16365375).

Almost surely, 2^65425981 is an apocalyptic number.

It is an amenable number.

65425981 is a deficient number, since it is larger than the sum of its proper divisors (35519).

65425981 is a wasteful number, since it uses less digits than its factorization.

65425981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35518.

The product of its digits is 86400, while the sum is 40.

The square root of 65425981 is about 8088.6328263805. The cubic root of 65425981 is about 402.9489988350.

The spelling of 65425981 in words is "sixty-five million, four hundred twenty-five thousand, nine hundred eighty-one".