1551165665500 has 48 divisors (see below), whose sum is σ = 3695722718688. Its totient is φ = 564060240000.

The previous prime is 1551165665453. The next prime is 1551165665507. The reversal of 1551165665500 is 55665611551.

It is a happy number.

It is a super-2 number, since 2×1551165665500² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1551165665507) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 141009561 + ... + 141020560.

It is an arithmetic number, because the mean of its divisors is an integer number (76994223306).

Almost surely, 2^{1551165665500} is an apocalyptic number.

1551165665500 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1551165665500 is an abundant number, since it is smaller than the sum of its proper divisors (2144557053188).

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

1551165665500 is a wasteful number, since it uses less digits than its factorization.

1551165665500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 282030151 (or 282030139 counting only the distinct ones).

The product of its (nonzero) digits is 675000, while the sum is 46.

The spelling of 1551165665500 in words is "one trillion, five hundred fifty-one billion, one hundred sixty-five million, six hundred sixty-five thousand, five hundred".