21025243430 has 32 divisors (see below), whose sum is σ = 38035720800. Its totient is φ = 8367907072.

The previous prime is 21025243417. The next prime is 21025243433. The reversal of 21025243430 is 3434252012.

It is a super-2 number, since 2×21025243430² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21025243430.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21025243433) 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, 1925426 + ... + 1936314.

It is an arithmetic number, because the mean of its divisors is an integer number (1188616275).

Almost surely, 2^21025243430 is an apocalyptic number.

21025243430 is a deficient number, since it is larger than the sum of its proper divisors (17010477370).

21025243430 is a wasteful number, since it uses less digits than its factorization.

21025243430 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11848.

The product of its (nonzero) digits is 5760, while the sum is 26.

Adding to 21025243430 its reverse (3434252012), we get a palindrome (24459495442).

The spelling of 21025243430 in words is "twenty-one billion, twenty-five million, two hundred forty-three thousand, four hundred thirty".