21201010031 has 4 divisors (see below), whose sum is σ = 21205626552. Its totient is φ = 21196393512.

The previous prime is 21201010007. The next prime is 21201010057. The reversal of 21201010031 is 13001010212.

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 21201010031 - 2⁶ = 21201009967 is a prime.

It is a super-2 number, since 2×21201010031² (a number of 21 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 = 21201009994 and 21201010021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21201010631) 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, 2301365 + ... + 2310558.

It is an arithmetic number, because the mean of its divisors is an integer number (5301406638).

Almost surely, 2^21201010031 is an apocalyptic number.

21201010031 is a deficient number, since it is larger than the sum of its proper divisors (4616521).

21201010031 is an equidigital number, since it uses as much as digits as its factorization.

21201010031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4616520.

The product of its (nonzero) digits is 12, while the sum is 11.

Adding to 21201010031 its reverse (13001010212), we get a palindrome (34202020243).

The spelling of 21201010031 in words is "twenty-one billion, two hundred one million, ten thousand, thirty-one".