31151221020055 has 4 divisors (see below), whose sum is σ = 37381465224072. Its totient is φ = 24920976816040.

The previous prime is 31151221020019. The next prime is 31151221020067. The reversal of 31151221020055 is 55002012215113.

It is a happy number.

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

It is not a de Polignac number, because 31151221020055 - 2³³ = 31142631085463 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3115122102001 + ... + 3115122102010.

It is an arithmetic number, because the mean of its divisors is an integer number (9345366306018).

Almost surely, 2^{31151221020055} is an apocalyptic number.

31151221020055 is a deficient number, since it is larger than the sum of its proper divisors (6230244204017).

31151221020055 is an equidigital number, since it uses as much as digits as its factorization.

31151221020055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6230244204016.

The product of its (nonzero) digits is 3000, while the sum is 28.

Adding to 31151221020055 its reverse (55002012215113), we get a palindrome (86153233235168).

The spelling of 31151221020055 in words is "thirty-one trillion, one hundred fifty-one billion, two hundred twenty-one million, twenty thousand, fifty-five".