312640042 has 24 divisors (see below), whose sum is σ = 555125508. Its totient is φ = 131176320.

The previous prime is 312640019. The next prime is 312640043. The reversal of 312640042 is 240046213.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 233447841 + 79192201 = 15279^2 + 8899^2 .

It is a super-3 number, since 3×312640042³ (a number of 26 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a junction number, because it is equal to n+sod(n) for n = 312639995 and 312640022.

It is not an unprimeable number, because it can be changed into a prime (312640043) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 46543 + ... + 52834.

Almost surely, 2^312640042 is an apocalyptic number.

312640042 is a deficient number, since it is larger than the sum of its proper divisors (242485466).

312640042 is a wasteful number, since it uses less digits than its factorization.

312640042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99414 (or 99403 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 22.

The square root of 312640042 is about 17681.6300719136. The cubic root of 312640042 is about 678.7057576694.

Adding to 312640042 its reverse (240046213), we get a palindrome (552686255).

The spelling of 312640042 in words is "three hundred twelve million, six hundred forty thousand, forty-two".