31515402104042 has 4 divisors (see below), whose sum is σ = 47273103156066. Its totient is φ = 15757701052020.

The previous prime is 31515402104029. The next prime is 31515402104101. The reversal of 31515402104042 is 24040120451513.

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

It can be written as a sum of positive squares in only one way, i.e., 27837748270201 + 3677653833841 = 5276149^2 + 1917721^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7878850526009 + ... + 7878850526012.

Almost surely, 2^{31515402104042} is an apocalyptic number.

31515402104042 is a deficient number, since it is larger than the sum of its proper divisors (15757701052024).

31515402104042 is a wasteful number, since it uses less digits than its factorization.

31515402104042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15757701052023.

The product of its (nonzero) digits is 19200, while the sum is 32.

Adding to 31515402104042 its reverse (24040120451513), we get a palindrome (55555522555555).

The spelling of 31515402104042 in words is "thirty-one trillion, five hundred fifteen billion, four hundred two million, one hundred four thousand, forty-two".