21023002455 has 128 divisors (see below), whose sum is σ = 43795648512. Its totient is φ = 8368386048.

The previous prime is 21023002453. The next prime is 21023002459. The reversal of 21023002455 is 55420032012.

It is not a de Polignac number, because 21023002455 - 2¹ = 21023002453 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21023002453) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 2287249 + ... + 2296421.

It is an arithmetic number, because the mean of its divisors is an integer number (342153504).

Almost surely, 2^21023002455 is an apocalyptic number.

21023002455 is an abundant number, since it is smaller than the sum of its proper divisors (22772646057).

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

21023002455 is a wasteful number, since it uses less digits than its factorization.

21023002455 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9297.

The product of its (nonzero) digits is 2400, while the sum is 24.

Adding to 21023002455 its reverse (55420032012), we get a palindrome (76443034467).

The spelling of 21023002455 in words is "twenty-one billion, twenty-three million, two thousand, four hundred fifty-five".