21102102031 has 16 divisors (see below), whose sum is σ = 23403594240. Its totient is φ = 18936577440.

The previous prime is 21102101987. The next prime is 21102102041. The reversal of 21102102031 is 13020120112.

It is a cyclic number.

It is not a de Polignac number, because 21102102031 - 2⁹ = 21102101519 is a prime.

It is a super-2 number, since 2×21102102031² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21102102041) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 189400 + ... + 279421.

It is an arithmetic number, because the mean of its divisors is an integer number (1462724640).

Almost surely, 2^21102102031 is an apocalyptic number.

21102102031 is a deficient number, since it is larger than the sum of its proper divisors (2301492209).

21102102031 is a wasteful number, since it uses less digits than its factorization.

21102102031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 468966.

The product of its (nonzero) digits is 24, while the sum is 13.

Adding to 21102102031 its reverse (13020120112), we get a palindrome (34122222143).

The spelling of 21102102031 in words is "twenty-one billion, one hundred two million, one hundred two thousand, thirty-one".