21869395280 has 20 divisors (see below), whose sum is σ = 50846344212. Its totient is φ = 8747758080.

The previous prime is 21869395277. The next prime is 21869395283. The reversal of 21869395280 is 8259396812.

It is an interprime number because it is at equal distance from previous prime (21869395277) and next prime (21869395283).

It can be written as a sum of positive squares in 2 ways, for example, as 15878016064 + 5991379216 = 126008^2 + 77404^2 .

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 (21869395283) 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, 136683641 + ... + 136683800.

Almost surely, 2^21869395280 is an apocalyptic number.

21869395280 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21869395280 is an abundant number, since it is smaller than the sum of its proper divisors (28976948932).

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

21869395280 is a wasteful number, since it uses less digits than its factorization.

21869395280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 273367454 (or 273367448 counting only the distinct ones).

The product of its (nonzero) digits is 1866240, while the sum is 53.

The spelling of 21869395280 in words is "twenty-one billion, eight hundred sixty-nine million, three hundred ninety-five thousand, two hundred eighty".