21002220031 has 8 divisors (see below), whose sum is σ = 22655045504. Its totient is φ = 19354718880.

The previous prime is 21002220017. The next prime is 21002220097. The reversal of 21002220031 is 13002220012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21002220031 - 2⁵ = 21002219999 is a prime.

It is a super-2 number, since 2×21002220031² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a junction number, because it is equal to n+sod(n) for n = 21002219993 and 21002220020.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21002220431) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1322880 + ... + 1338661.

It is an arithmetic number, because the mean of its divisors is an integer number (2831880688).

Almost surely, 2^21002220031 is an apocalyptic number.

21002220031 is a deficient number, since it is larger than the sum of its proper divisors (1652825473).

21002220031 is a wasteful number, since it uses less digits than its factorization.

21002220031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2662161.

The product of its (nonzero) digits is 48, while the sum is 13.

Adding to 21002220031 its reverse (13002220012), we get a palindrome (34004440043).

The spelling of 21002220031 in words is "twenty-one billion, two million, two hundred twenty thousand, thirty-one".