402981506 has 8 divisors (see below), whose sum is σ = 625316220. Its totient is φ = 194542768.

The previous prime is 402981503. The next prime is 402981511. The reversal of 402981506 is 605189204.

It can be written as a sum of positive squares in 2 ways, for example, as 393427225 + 9554281 = 19835^2 + 3091^2 .

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

It is not an unprimeable number, because it can be changed into a prime (402981503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3473921 + ... + 3474036.

Almost surely, 2^402981506 is an apocalyptic number.

402981506 is a deficient number, since it is larger than the sum of its proper divisors (222334714).

402981506 is a wasteful number, since it uses less digits than its factorization.

402981506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6947988.

The product of its (nonzero) digits is 17280, while the sum is 35.

The square root of 402981506 is about 20074.3992687203. The cubic root of 402981506 is about 738.6324303689.

The spelling of 402981506 in words is "four hundred two million, nine hundred eighty-one thousand, five hundred six".