21220000031 has 8 divisors (see below), whose sum is σ = 22906147680. Its totient is φ = 19597480672.

The previous prime is 21220000019. The next prime is 21220000037. The reversal of 21220000031 is 13000002212.

It is a happy number.

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 21220000031 - 2²⁶ = 21152891167 is a prime.

It is a super-2 number, since 2×21220000031² (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 = 21219999967 and 21220000021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21220000037) 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, 15906380 + ... + 15907713.

It is an arithmetic number, because the mean of its divisors is an integer number (2863268460).

Almost surely, 2^21220000031 is an apocalyptic number.

21220000031 is a deficient number, since it is larger than the sum of its proper divisors (1686147649).

21220000031 is a wasteful number, since it uses less digits than its factorization.

21220000031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31814145.

The product of its (nonzero) digits is 24, while the sum is 11.

Adding to 21220000031 its reverse (13000002212), we get a palindrome (34220002243).

The spelling of 21220000031 in words is "twenty-one billion, two hundred twenty million, thirty-one", and thus it is an aban number.