31002220121 has 4 divisors (see below), whose sum is σ = 31047086544. Its totient is φ = 30957353700.

The previous prime is 31002220111. The next prime is 31002220133. The reversal of 31002220121 is 12102220013.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 31002220121 - 2⁶ = 31002220057 is a prime.

It is a super-2 number, since 2×31002220121² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31002220096 and 31002220105.

It is not an unprimeable number, because it can be changed into a prime (31002220111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22432175 + ... + 22433556.

It is an arithmetic number, because the mean of its divisors is an integer number (7761771636).

Almost surely, 2^31002220121 is an apocalyptic number.

It is an amenable number.

31002220121 is a deficient number, since it is larger than the sum of its proper divisors (44866423).

31002220121 is an equidigital number, since it uses as much as digits as its factorization.

31002220121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44866422.

The product of its (nonzero) digits is 48, while the sum is 14.

Adding to 31002220121 its reverse (12102220013), we get a palindrome (43104440134).

The spelling of 31002220121 in words is "thirty-one billion, two million, two hundred twenty thousand, one hundred twenty-one".