21133313740 has 96 divisors (see below), whose sum is σ = 55402357248. Its totient is φ = 6578496000.

The previous prime is 21133313701. The next prime is 21133313741. The reversal of 21133313740 is 4731333112.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a junction number, because it is equal to n+sod(n) for n = 21133313699 and 21133313708.

It is not an unprimeable number, because it can be changed into a prime (21133313741) 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, 1240480 + ... + 1257400.

It is an arithmetic number, because the mean of its divisors is an integer number (577107888).

Almost surely, 2^21133313740 is an apocalyptic number.

21133313740 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 21133313740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27701178624).

21133313740 is an abundant number, since it is smaller than the sum of its proper divisors (34269043508).

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

21133313740 is a wasteful number, since it uses less digits than its factorization.

21133313740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17759 (or 17757 counting only the distinct ones).

The product of its (nonzero) digits is 4536, while the sum is 28.

Adding to 21133313740 its reverse (4731333112), we get a palindrome (25864646852).

The spelling of 21133313740 in words is "twenty-one billion, one hundred thirty-three million, three hundred thirteen thousand, seven hundred forty".