21430015280 has 40 divisors (see below), whose sum is σ = 49841040624. Its totient is φ = 8569209600.

The previous prime is 21430015273. The next prime is 21430015301. The reversal of 21430015280 is 8251003412.

It is a tau number, because it is divible by the number of its divisors (40).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 212375 + ... + 296585.

Almost surely, 2^21430015280 is an apocalyptic number.

21430015280 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21430015280 is an abundant number, since it is smaller than the sum of its proper divisors (28411025344).

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

21430015280 is a wasteful number, since it uses less digits than its factorization.

21430015280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87405 (or 87399 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 26.

Adding to 21430015280 its reverse (8251003412), we get a palindrome (29681018692).

The spelling of 21430015280 in words is "twenty-one billion, four hundred thirty million, fifteen thousand, two hundred eighty".