65621213823 has 16 divisors (see below), whose sum is σ = 96433053696. Its totient is φ = 39360426240.

The previous prime is 65621213821. The next prime is 65621213837. The reversal of 65621213823 is 32831212656.

It is a happy number.

It is not a de Polignac number, because 65621213823 - 2¹ = 65621213821 is a prime.

It is a super-2 number, since 2×65621213823² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65621213821) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10246911 + ... + 10253312.

It is an arithmetic number, because the mean of its divisors is an integer number (6027065856).

Almost surely, 2^65621213823 is an apocalyptic number.

65621213823 is a deficient number, since it is larger than the sum of its proper divisors (30811839873).

65621213823 is a wasteful number, since it uses less digits than its factorization.

65621213823 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20500334.

The product of its digits is 103680, while the sum is 39.

The spelling of 65621213823 in words is "sixty-five billion, six hundred twenty-one million, two hundred thirteen thousand, eight hundred twenty-three".