653661235462681 has 4 divisors (see below), whose sum is σ = 653707829049700. Its totient is φ = 653614641875664.

The previous prime is 653661235462643. The next prime is 653661235462699. The reversal of 653661235462681 is 186264532166356.

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 8867197550656 + 644794037912025 = 2977784^2 + 25392795^2 .

It is a cyclic number.

It is not a de Polignac number, because 653661235462681 - 2¹³ = 653661235454489 is a prime.

It is a super-2 number, since 2×653661235462681² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (653661035462681) 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, 23296772466 + ... + 23296800523.

It is an arithmetic number, because the mean of its divisors is an integer number (163426957262425).

Almost surely, 2^{653661235462681} is an apocalyptic number.

It is an amenable number.

653661235462681 is a deficient number, since it is larger than the sum of its proper divisors (46593587019).

653661235462681 is a wasteful number, since it uses less digits than its factorization.

653661235462681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46593587018.

The product of its digits is 223948800, while the sum is 64.

The spelling of 653661235462681 in words is "six hundred fifty-three trillion, six hundred sixty-one billion, two hundred thirty-five million, four hundred sixty-two thousand, six hundred eighty-one".