65731230121 has 4 divisors (see below), whose sum is σ = 67507749892. Its totient is φ = 63954710352.

The previous prime is 65731230119. The next prime is 65731230157. The reversal of 65731230121 is 12103213756.

It is a happy number.

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 48547952896 + 17183277225 = 220336^2 + 131085^2 .

It is a cyclic number.

It is not a de Polignac number, because 65731230121 - 2¹ = 65731230119 is a prime.

It is a super-2 number, since 2×65731230121² (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 (65731230421) 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, 888259830 + ... + 888259903.

It is an arithmetic number, because the mean of its divisors is an integer number (16876937473).

Almost surely, 2^65731230121 is an apocalyptic number.

It is an amenable number.

65731230121 is a deficient number, since it is larger than the sum of its proper divisors (1776519771).

65731230121 is a wasteful number, since it uses less digits than its factorization.

65731230121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1776519770.

The product of its (nonzero) digits is 7560, while the sum is 31.

Adding to 65731230121 its reverse (12103213756), we get a palindrome (77834443877).

The spelling of 65731230121 in words is "sixty-five billion, seven hundred thirty-one million, two hundred thirty thousand, one hundred twenty-one".