21203120310 has 32 divisors (see below), whose sum is σ = 50898903552. Its totient is φ = 5652897120.

The previous prime is 21203120299. The next prime is 21203120347. The reversal of 21203120310 is 1302130212.

It is a super-2 number, since 2×21203120310² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21203120310.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 60757 + ... + 214703.

It is an arithmetic number, because the mean of its divisors is an integer number (1590590736).

Almost surely, 2^21203120310 is an apocalyptic number.

21203120310 is an abundant number, since it is smaller than the sum of its proper divisors (29695783242).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21203120310 is a wasteful number, since it uses less digits than its factorization.

21203120310 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 158548.

The product of its (nonzero) digits is 72, while the sum is 15.

Adding to 21203120310 its reverse (1302130212), we get a palindrome (22505250522).

The spelling of 21203120310 in words is "twenty-one billion, two hundred three million, one hundred twenty thousand, three hundred ten".