65721070501 has 4 divisors (see below), whose sum is σ = 66621359212. Its totient is φ = 64820781792.

The previous prime is 65721070489. The next prime is 65721070511. The reversal of 65721070501 is 10507012756.

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 12740539876 + 52980530625 = 112874^2 + 230175^2 .

It is a cyclic number.

It is not a de Polignac number, because 65721070501 - 2³³ = 57131135909 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 (65721070511) 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, 450144246 + ... + 450144391.

It is an arithmetic number, because the mean of its divisors is an integer number (16655339803).

Almost surely, 2^65721070501 is an apocalyptic number.

It is an amenable number.

65721070501 is a deficient number, since it is larger than the sum of its proper divisors (900288711).

65721070501 is an equidigital number, since it uses as much as digits as its factorization.

65721070501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 900288710.

The product of its (nonzero) digits is 14700, while the sum is 34.

The spelling of 65721070501 in words is "sixty-five billion, seven hundred twenty-one million, seventy thousand, five hundred one".