15551144400 has 480 divisors, whose sum is σ = 59127608448. Its totient is φ = 3450470400.

The previous prime is 15551144381. The next prime is 15551144419. The reversal of 15551144400 is 444115551.

It is an interprime number because it is at equal distance from previous prime (15551144381) and next prime (15551144419).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 8301864 + ... + 8303736.

Almost surely, 2^15551144400 is an apocalyptic number.

15551144400 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 15551144400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29563804224).

15551144400 is an abundant number, since it is smaller than the sum of its proper divisors (43576464048).

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

15551144400 is a wasteful number, since it uses less digits than its factorization.

15551144400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1959 (or 1948 counting only the distinct ones).

The product of its (nonzero) digits is 8000, while the sum is 30.

Adding to 15551144400 its reverse (444115551), we get a palindrome (15995259951).

It can be divided in two parts, 15551 and 144400, that added together give a palindrome (159951).

The spelling of 15551144400 in words is "fifteen billion, five hundred fifty-one million, one hundred forty-four thousand, four hundred".