21493095280 has 20 divisors (see below), whose sum is σ = 49971446712. Its totient is φ = 8597238080.

The previous prime is 21493095277. The next prime is 21493095287. The reversal of 21493095280 is 8259039412.

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21493095287) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 134331766 + ... + 134331925.

Almost surely, 2^21493095280 is an apocalyptic number.

21493095280 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21493095280 is an abundant number, since it is smaller than the sum of its proper divisors (28478351432).

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

21493095280 is a wasteful number, since it uses less digits than its factorization.

21493095280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 268663704 (or 268663698 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 43.

The spelling of 21493095280 in words is "twenty-one billion, four hundred ninety-three million, ninety-five thousand, two hundred eighty".