21405601360 has 160 divisors (see below), whose sum is σ = 61011595008. Its totient is φ = 6872616960.

The previous prime is 21405601333. The next prime is 21405601367. The reversal of 21405601360 is 6310650412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21405601367) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 222444 + ... + 303796.

Almost surely, 2^21405601360 is an apocalyptic number.

21405601360 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21405601360, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30505797504).

21405601360 is an abundant number, since it is smaller than the sum of its proper divisors (39605993648).

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

21405601360 is a wasteful number, since it uses less digits than its factorization.

21405601360 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81413 (or 81407 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 28.

The spelling of 21405601360 in words is "twenty-one billion, four hundred five million, six hundred one thousand, three hundred sixty".