15551500023440 has 80 divisors (see below), whose sum is σ = 36826910962560. Its totient is φ = 6105713341440.

The previous prime is 15551500023419. The next prime is 15551500023443. The reversal of 15551500023440 is 4432000515551.

It is a tau number, because it is divible by the number of its divisors (80).

It is a self number, because there is not a number n which added to its sum of digits gives 15551500023440.

It is not an unprimeable number, because it can be changed into a prime (15551500023443) 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, 507620 + ... + 5600060.

It is an arithmetic number, because the mean of its divisors is an integer number (460336387032).

Almost surely, 2^{15551500023440} is an apocalyptic number.

15551500023440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 15551500023440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18413455481280).

15551500023440 is an abundant number, since it is smaller than the sum of its proper divisors (21275410939120).

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

15551500023440 is a wasteful number, since it uses less digits than its factorization.

15551500023440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5093160 (or 5093154 counting only the distinct ones).

The product of its (nonzero) digits is 60000, while the sum is 35.

Adding to 15551500023440 its reverse (4432000515551), we get a palindrome (19983500538991).

The spelling of 15551500023440 in words is "fifteen trillion, five hundred fifty-one billion, five hundred million, twenty-three thousand, four hundred forty".