1981430578 has 8 divisors (see below), whose sum is σ = 2973299868. Its totient is φ = 990330624.

The previous prime is 1981430569. The next prime is 1981430579. The reversal of 1981430578 is 8750341891.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 1981407169 + 23409 = 44513^2 + 153^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-3 number, since 3×1981430578³ (a number of 29 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (1981430579) 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, 185851 + ... + 196222.

Almost surely, 2^1981430578 is an apocalyptic number.

1981430578 is a deficient number, since it is larger than the sum of its proper divisors (991869290).

1981430578 is a wasteful number, since it uses less digits than its factorization.

1981430578 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 384668.

The product of its (nonzero) digits is 241920, while the sum is 46.

The square root of 1981430578 is about 44513.2629448797. The cubic root of 1981430578 is about 1256.0095849168.

The spelling of 1981430578 in words is "one billion, nine hundred eighty-one million, four hundred thirty thousand, five hundred seventy-eight".