1555998 has 32 divisors (see below), whose sum is σ = 3290496. Its totient is φ = 489888.

The previous prime is 1555997. The next prime is 1555999. The reversal of 1555998 is 8995551.

It is a happy number.

1555998 is nontrivially palindromic in base 5.

It is an interprime number because it is at equal distance from previous prime (1555997) and next prime (1555999).

It is a super-2 number, since 2×1555998² = 4842259552008, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1555997) 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, 9465 + ... + 9627.

It is an arithmetic number, because the mean of its divisors is an integer number (102828).

2^1555998 is an apocalyptic number.

1555998 is an abundant number, since it is smaller than the sum of its proper divisors (1734498).

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

1555998 is a wasteful number, since it uses less digits than its factorization.

1555998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 248.

The product of its digits is 81000, while the sum is 42.

The square root of 1555998 is about 1247.3964886915. The cubic root of 1555998 is about 115.8785391359.

The spelling of 1555998 in words is "one million, five hundred fifty-five thousand, nine hundred ninety-eight".