15550000 has 60 divisors (see below), whose sum is σ = 37778832. Its totient is φ = 6200000.

The previous prime is 15549983. The next prime is 15550009. The reversal of 15550000 is 5551.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is not an unprimeable number, because it can be changed into a prime (15550009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 49845 + ... + 50155.

Almost surely, 2^15550000 is an apocalyptic number.

15550000 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 15550000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18889416).

15550000 is an abundant number, since it is smaller than the sum of its proper divisors (22228832).

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

15550000 is an frugal number, since it uses more digits than its factorization.

15550000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 344 (or 318 counting only the distinct ones).

The product of its (nonzero) digits is 125, while the sum is 16.

The square root of 15550000 is about 3943.3488306261. The cubic root of 15550000 is about 249.5993582879.

Adding to 15550000 its reverse (5551), we get a palindrome (15555551).

The spelling of 15550000 in words is "fifteen million, five hundred fifty thousand".