21021231010 has 32 divisors (see below), whose sum is σ = 40755706992. Its totient is φ = 7760378880.

The previous prime is 21021230981. The next prime is 21021231013. The reversal of 21021231010 is 1013212012.

It can be written as a sum of positive squares in 8 ways, for example, as 3112635681 + 17908595329 = 55791^2 + 133823^2 .

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

It is not an unprimeable number, because it can be changed into a prime (21021231013) 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, 1129702 + ... + 1148158.

Almost surely, 2^21021231010 is an apocalyptic number.

21021231010 is a deficient number, since it is larger than the sum of its proper divisors (19734475982).

21021231010 is a wasteful number, since it uses less digits than its factorization.

21021231010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27238.

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

Adding to 21021231010 its reverse (1013212012), we get a palindrome (22034443022).

The spelling of 21021231010 in words is "twenty-one billion, twenty-one million, two hundred thirty-one thousand, ten".