21120200031031 has 4 divisors (see below), whose sum is σ = 21120418102392. Its totient is φ = 21119981959672.

The previous prime is 21120200030999. The next prime is 21120200031059. The reversal of 21120200031031 is 13013000202112.

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

It is a cyclic number.

It is not a de Polignac number, because 21120200031031 - 2⁵ = 21120200030999 is a prime.

It is a super-2 number, since 2×21120200031031² (a number of 27 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 = 21120200030996 and 21120200031014.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21120200071031) 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, 108890341 + ... + 109084126.

It is an arithmetic number, because the mean of its divisors is an integer number (5280104525598).

Almost surely, 2^{21120200031031} is an apocalyptic number.

21120200031031 is a deficient number, since it is larger than the sum of its proper divisors (218071361).

21120200031031 is an equidigital number, since it uses as much as digits as its factorization.

21120200031031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 218071360.

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 21120200031031 its reverse (13013000202112), we get a palindrome (34133200233143).

The spelling of 21120200031031 in words is "twenty-one trillion, one hundred twenty billion, two hundred million, thirty-one thousand, thirty-one".