65850723921 has 4 divisors (see below), whose sum is σ = 87800965232. Its totient is φ = 43900482612.

The previous prime is 65850723901. The next prime is 65850723923. The reversal of 65850723921 is 12932705856.

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 not a de Polignac number, because 65850723921 - 2¹⁷ = 65850592849 is a prime.

It is a super-2 number, since 2×65850723921² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65850723923) 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, 10975120651 + ... + 10975120656.

It is an arithmetic number, because the mean of its divisors is an integer number (21950241308).

Almost surely, 2^65850723921 is an apocalyptic number.

It is an amenable number.

65850723921 is a deficient number, since it is larger than the sum of its proper divisors (21950241311).

65850723921 is a wasteful number, since it uses less digits than its factorization.

65850723921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21950241310.

The product of its (nonzero) digits is 907200, while the sum is 48.

The spelling of 65850723921 in words is "sixty-five billion, eight hundred fifty million, seven hundred twenty-three thousand, nine hundred twenty-one".