21421311340 has 96 divisors (see below), whose sum is σ = 52888530240. Its totient is φ = 7185024000.

The previous prime is 21421311323. The next prime is 21421311383. The reversal of 21421311340 is 4311312412.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6487690 + ... + 6490990.

It is an arithmetic number, because the mean of its divisors is an integer number (550922190).

Almost surely, 2^21421311340 is an apocalyptic number.

21421311340 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 21421311340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26444265120).

21421311340 is an abundant number, since it is smaller than the sum of its proper divisors (31467218900).

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

21421311340 is a wasteful number, since it uses less digits than its factorization.

21421311340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5603 (or 5601 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 22.

Adding to 21421311340 its reverse (4311312412), we get a palindrome (25732623752).

The spelling of 21421311340 in words is "twenty-one billion, four hundred twenty-one million, three hundred eleven thousand, three hundred forty".