655685099551 has 4 divisors (see below), whose sum is σ = 678294930600. Its totient is φ = 633075268504.

The previous prime is 655685099549. The next prime is 655685099567. The reversal of 655685099551 is 155990586556.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 655685099551 - 2¹ = 655685099549 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 (655625099551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11304915481 + ... + 11304915538.

It is an arithmetic number, because the mean of its divisors is an integer number (169573732650).

Almost surely, 2^655685099551 is an apocalyptic number.

655685099551 is a deficient number, since it is larger than the sum of its proper divisors (22609831049).

655685099551 is a wasteful number, since it uses less digits than its factorization.

655685099551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22609831048.

The product of its (nonzero) digits is 72900000, while the sum is 64.

The spelling of 655685099551 in words is "six hundred fifty-five billion, six hundred eighty-five million, ninety-nine thousand, five hundred fifty-one".