1551661101108 has 36 divisors (see below), whose sum is σ = 3923108088900. Its totient is φ = 517107799296.

The previous prime is 1551661101083. The next prime is 1551661101173. The reversal of 1551661101108 is 8011011661551.

It is a happy number.

1551661101108 is a `hidden beast` number, since 15 + 5 + 16 + 611 + 0 + 1 + 10 + 8 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 494338360464 + 1057322740644 = 703092^2 + 1028262^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4522533 + ... + 4853516.

Almost surely, 2^{1551661101108} is an apocalyptic number.

1551661101108 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

1551661101108 is an abundant number, since it is smaller than the sum of its proper divisors (2371446987792).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1551661101108 is a wasteful number, since it uses less digits than its factorization.

1551661101108 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9380656 (or 9380651 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 36.

Adding to 1551661101108 its reverse (8011011661551), we get a palindrome (9562672762659).

The spelling of 1551661101108 in words is "one trillion, five hundred fifty-one billion, six hundred sixty-one million, one hundred one thousand, one hundred eight".