65921957 has 4 divisors (see below), whose sum is σ = 66562080. Its totient is φ = 65281836.

The previous prime is 65921953. The next prime is 65921969. The reversal of 65921957 is 75912956.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 65921957 - 2² = 65921953 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 (65921953) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 319907 + ... + 320112.

It is an arithmetic number, because the mean of its divisors is an integer number (16640520).

Almost surely, 2^65921957 is an apocalyptic number.

It is an amenable number.

65921957 is a deficient number, since it is larger than the sum of its proper divisors (640123).

65921957 is a wasteful number, since it uses less digits than its factorization.

65921957 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 640122.

The product of its digits is 170100, while the sum is 44.

The square root of 65921957 is about 8119.2337692667. The cubic root of 65921957 is about 403.9646511077.

Subtracting 65921957 from its reverse (75912956), we obtain a palindrome (9990999).

The spelling of 65921957 in words is "sixty-five million, nine hundred twenty-one thousand, nine hundred fifty-seven".