1551515615540 has 48 divisors (see below), whose sum is σ = 3560179875840. Its totient is φ = 563267076480.

The previous prime is 1551515615527. The next prime is 1551515615549. The reversal of 1551515615540 is 455165151551.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a junction number, because it is equal to n+sod(n) for n = 1551515615491 and 1551515615500.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1551515615549) 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, 5617460 + ... + 5887179.

It is an arithmetic number, because the mean of its divisors is an integer number (74170414080).

Almost surely, 2^{1551515615540} is an apocalyptic number.

1551515615540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1551515615540 is an abundant number, since it is smaller than the sum of its proper divisors (2008664260300).

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

1551515615540 is a wasteful number, since it uses less digits than its factorization.

1551515615540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11505272 (or 11505270 counting only the distinct ones).

The product of its (nonzero) digits is 375000, while the sum is 44.

The spelling of 1551515615540 in words is "one trillion, five hundred fifty-one billion, five hundred fifteen million, six hundred fifteen thousand, five hundred forty".