31143103021 has 4 divisors (see below), whose sum is σ = 31145220252. Its totient is φ = 31140985792.

The previous prime is 31143103003. The next prime is 31143103027. The reversal of 31143103021 is 12030134113.

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 9882546921 + 21260556100 = 99411^2 + 145810^2 .

It is a cyclic number.

It is not a de Polignac number, because 31143103021 - 2⁵ = 31143102989 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 31143103021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31143103027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1036396 + ... + 1066021.

It is an arithmetic number, because the mean of its divisors is an integer number (7786305063).

Almost surely, 2^31143103021 is an apocalyptic number.

It is an amenable number.

31143103021 is a deficient number, since it is larger than the sum of its proper divisors (2117231).

31143103021 is a wasteful number, since it uses less digits than its factorization.

31143103021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2117230.

The product of its (nonzero) digits is 216, while the sum is 19.

Adding to 31143103021 its reverse (12030134113), we get a palindrome (43173237134).

The spelling of 31143103021 in words is "thirty-one billion, one hundred forty-three million, one hundred three thousand, twenty-one".