1981402 has 16 divisors (see below), whose sum is σ = 3069000. Its totient is φ = 959040.

The previous prime is 1981393. The next prime is 1981403. The reversal of 1981402 is 2041891.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 938961 + 1042441 = 969^2 + 1021^2 .

It is a super-3 number, since 3×1981402³ = 23336678642530610424, which contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (1981403) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13224 + ... + 13372.

2^1981402 is an apocalyptic number.

1981402 is a deficient number, since it is larger than the sum of its proper divisors (1087598).

1981402 is a wasteful number, since it uses less digits than its factorization.

1981402 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 321.

The product of its (nonzero) digits is 576, while the sum is 25.

The square root of 1981402 is about 1407.6228187977. The cubic root of 1981402 is about 125.6003546449.

It can be divided in two parts, 198 and 1402, that added together give a square (1600 = 40²).

The spelling of 1981402 in words is "one million, nine hundred eighty-one thousand, four hundred two".