21023402130 has 96 divisors (see below), whose sum is σ = 55816463664. Its totient is φ = 5488846848.

The previous prime is 21023402119. The next prime is 21023402137. The reversal of 21023402130 is 3120432012.

21023402130 is a `hidden beast` number, since 210 + 23 + 402 + 1 + 30 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 14121281889 + 6902120241 = 118833^2 + 83079^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (21023402137) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 888412 + ... + 911768.

Almost surely, 2^21023402130 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21023402130, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27908231832).

21023402130 is an abundant number, since it is smaller than the sum of its proper divisors (34793061534).

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

21023402130 is a wasteful number, since it uses less digits than its factorization.

21023402130 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23580 (or 23577 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

Adding to 21023402130 its reverse (3120432012), we get a palindrome (24143834142).

The spelling of 21023402130 in words is "twenty-one billion, twenty-three million, four hundred two thousand, one hundred thirty".