31212402101 has 4 divisors (see below), whose sum is σ = 33048425772. Its totient is φ = 29376378432.

The previous prime is 31212402097. The next prime is 31212402107. The reversal of 31212402101 is 10120421213.

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 28442485201 + 2769916900 = 168649^2 + 52630^2 .

It is a cyclic number.

It is not a de Polignac number, because 31212402101 - 2² = 31212402097 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (17), and also a Moran number because the ratio is a prime number: 1836023653 = 31212402101 / (3 + 1 + 2 + 1 + 2 + 4 + 0 + 2 + 1 + 0 + 1).

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 31212402101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31212402107) 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, 918011810 + ... + 918011843.

It is an arithmetic number, because the mean of its divisors is an integer number (8262106443).

Almost surely, 2^31212402101 is an apocalyptic number.

It is an amenable number.

31212402101 is a deficient number, since it is larger than the sum of its proper divisors (1836023671).

31212402101 is a wasteful number, since it uses less digits than its factorization.

31212402101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1836023670.

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 31212402101 its reverse (10120421213), we get a palindrome (41332823314).

The spelling of 31212402101 in words is "thirty-one billion, two hundred twelve million, four hundred two thousand, one hundred one".