21001102031 has 24 divisors (see below), whose sum is σ = 27856679760. Its totient is φ = 15638821632.

The previous prime is 21001102027. The next prime is 21001102091. The reversal of 21001102031 is 13020110012.

It is not a de Polignac number, because 21001102031 - 2² = 21001102027 is a prime.

It is a super-2 number, since 2×21001102031² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21001102091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 958841 + ... + 980498.

It is an arithmetic number, because the mean of its divisors is an integer number (1160694990).

Almost surely, 2^21001102031 is an apocalyptic number.

21001102031 is a deficient number, since it is larger than the sum of its proper divisors (6855577729).

21001102031 is a wasteful number, since it uses less digits than its factorization.

21001102031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1939383 (or 1939376 counting only the distinct ones).

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

Adding to 21001102031 its reverse (13020110012), we get a palindrome (34021212043).

The spelling of 21001102031 in words is "twenty-one billion, one million, one hundred two thousand, thirty-one".