31125121201 has 4 divisors (see below), whose sum is σ = 31197004132. Its totient is φ = 31053238272.

The previous prime is 31125121199. The next prime is 31125121213. The reversal of 31125121201 is 10212152113.

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

It can be written as a sum of positive squares in 2 ways, for example, as 15475111201 + 15650010000 = 124399^2 + 125100^2 .

It is a cyclic number.

It is not a de Polignac number, because 31125121201 - 2¹ = 31125121199 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31125121231) 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, 35940816 + ... + 35941681.

It is an arithmetic number, because the mean of its divisors is an integer number (7799251033).

Almost surely, 2^31125121201 is an apocalyptic number.

It is an amenable number.

31125121201 is a deficient number, since it is larger than the sum of its proper divisors (71882931).

31125121201 is an equidigital number, since it uses as much as digits as its factorization.

31125121201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71882930.

The product of its (nonzero) digits is 120, while the sum is 19.

Adding to 31125121201 its reverse (10212152113), we get a palindrome (41337273314).

The spelling of 31125121201 in words is "thirty-one billion, one hundred twenty-five million, one hundred twenty-one thousand, two hundred one".