551666655565 has 16 divisors (see below), whose sum is σ = 708265739520. Its totient is φ = 411251065920.

The previous prime is 551666655479. The next prime is 551666655571. The reversal of 551666655565 is 565556666155.

It is a happy number.

It is not a de Polignac number, because 551666655565 - 2¹³ = 551666647373 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (61).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 47592709 + ... + 47604298.

It is an arithmetic number, because the mean of its divisors is an integer number (44266608720).

Almost surely, 2^551666655565 is an apocalyptic number.

It is an amenable number.

551666655565 is a deficient number, since it is larger than the sum of its proper divisors (156599083955).

551666655565 is a wasteful number, since it uses less digits than its factorization.

551666655565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95197092.

The product of its digits is 121500000, while the sum is 61.

The spelling of 551666655565 in words is "five hundred fifty-one billion, six hundred sixty-six million, six hundred fifty-five thousand, five hundred sixty-five".