21011002452 has 240 divisors, whose sum is σ = 62209534464. Its totient is φ = 6128136000.

The previous prime is 21011002451. The next prime is 21011002469. The reversal of 21011002452 is 25420011012.

21011002452 is a `hidden beast` number, since 210 + 1 + 1 + 0 + 0 + 2 + 452 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21011002451) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 10879927 + ... + 10881857.

Almost surely, 2^21011002452 is an apocalyptic number.

21011002452 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21011002452, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31104767232).

21011002452 is an abundant number, since it is smaller than the sum of its proper divisors (41198532012).

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

21011002452 is a wasteful number, since it uses less digits than its factorization.

21011002452 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2072 (or 2061 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 18.

Adding to 21011002452 its reverse (25420011012), we get a palindrome (46431013464).

The spelling of 21011002452 in words is "twenty-one billion, eleven million, two thousand, four hundred fifty-two".