1988401 has 4 divisors (see below), whose sum is σ = 2025972. Its totient is φ = 1950832.

The previous prime is 1988353. The next prime is 1988411. The reversal of 1988401 is 1048891.

1988401 = 81² + 82² + ... + 186².

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1221025 + 767376 = 1105^2 + 876^2 .

It is a cyclic number.

It is not a de Polignac number, because 1988401 - 2⁹ = 1987889 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1988411) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18706 + ... + 18811.

It is an arithmetic number, because the mean of its divisors is an integer number (506493).

2^1988401 is an apocalyptic number.

It is an amenable number.

1988401 is a deficient number, since it is larger than the sum of its proper divisors (37571).

1988401 is an equidigital number, since it uses as much as digits as its factorization.

1988401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37570.

The product of its (nonzero) digits is 2304, while the sum is 31.

The square root of 1988401 is about 1410.1067335489. The cubic root of 1988401 is about 125.7480688796.

The spelling of 1988401 in words is "one million, nine hundred eighty-eight thousand, four hundred one".