21603261120 has 336 divisors, whose sum is σ = 80076312288. Its totient is φ = 4920115200.

The previous prime is 21603261109. The next prime is 21603261133. The reversal of 21603261120 is 2116230612.

It is a tau number, because it is divible by the number of its divisors (336).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 16604470 + ... + 16605770.

It is an arithmetic number, because the mean of its divisors is an integer number (238322358).

Almost surely, 2^21603261120 is an apocalyptic number.

21603261120 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 21603261120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40038156144).

21603261120 is an abundant number, since it is smaller than the sum of its proper divisors (58473051168).

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

21603261120 is a wasteful number, since it uses less digits than its factorization.

21603261120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1688 (or 1671 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 24.

Adding to 21603261120 its reverse (2116230612), we get a palindrome (23719491732).

The spelling of 21603261120 in words is "twenty-one billion, six hundred three million, two hundred sixty-one thousand, one hundred twenty".