31542440155 has 4 divisors (see below), whose sum is σ = 37850928192. Its totient is φ = 25233952120.

The previous prime is 31542440147. The next prime is 31542440159. The reversal of 31542440155 is 55104424513.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 55104424513 = 179 ⋅307845947.

It is not a de Polignac number, because 31542440155 - 2³ = 31542440147 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 31542440155.

It is not an unprimeable number, because it can be changed into a prime (31542440159) 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, 3154244011 + ... + 3154244020.

It is an arithmetic number, because the mean of its divisors is an integer number (9462732048).

Almost surely, 2^31542440155 is an apocalyptic number.

31542440155 is a deficient number, since it is larger than the sum of its proper divisors (6308488037).

31542440155 is an equidigital number, since it uses as much as digits as its factorization.

31542440155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6308488036.

The product of its (nonzero) digits is 48000, while the sum is 34.

Adding to 31542440155 its reverse (55104424513), we get a palindrome (86646864668).

The spelling of 31542440155 in words is "thirty-one billion, five hundred forty-two million, four hundred forty thousand, one hundred fifty-five".