15551998 has 16 divisors (see below), whose sum is σ = 29084544. Its totient is φ = 6059160.

The previous prime is 15551989. The next prime is 15551999. The reversal of 15551998 is 89915551.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15551999) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 50340 + ... + 50647.

It is an arithmetic number, because the mean of its divisors is an integer number (1817784).

Almost surely, 2^15551998 is an apocalyptic number.

15551998 is a deficient number, since it is larger than the sum of its proper divisors (13532546).

15551998 is a wasteful number, since it uses less digits than its factorization.

15551998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101007.

The product of its digits is 81000, while the sum is 43.

The square root of 15551998 is about 3943.6021604619. The cubic root of 15551998 is about 249.6100480662.

It can be divided in two parts, 1555 and 1998, that added together give a palindrome (3553).

The spelling of 15551998 in words is "fifteen million, five hundred fifty-one thousand, nine hundred ninety-eight".