53505857661 has 4 divisors (see below), whose sum is σ = 71341143552. Its totient is φ = 35670571772.

The previous prime is 53505857593. The next prime is 53505857677. The reversal of 53505857661 is 16675850535.

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 a cyclic number.

It is not a de Polignac number, because 53505857661 - 2¹⁰ = 53505856637 is a prime.

It is a super-3 number, since 3×53505857661³ (a number of 33 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (53505859661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8917642941 + ... + 8917642946.

It is an arithmetic number, because the mean of its divisors is an integer number (17835285888).

Almost surely, 2^53505857661 is an apocalyptic number.

It is an amenable number.

53505857661 is a deficient number, since it is larger than the sum of its proper divisors (17835285891).

53505857661 is a wasteful number, since it uses less digits than its factorization.

53505857661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17835285890.

The product of its (nonzero) digits is 3780000, while the sum is 51.

The spelling of 53505857661 in words is "fifty-three billion, five hundred five million, eight hundred fifty-seven thousand, six hundred sixty-one".