21340410340 has 12 divisors (see below), whose sum is σ = 44814861756. Its totient is φ = 8536164128.

The previous prime is 21340410317. The next prime is 21340410361. The reversal of 21340410340 is 4301404312.

It can be written as a sum of positive squares in 2 ways, for example, as 4989161956 + 16351248384 = 70634^2 + 127872^2 .

It is a super-2 number, since 2×21340410340² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 533510239 + ... + 533510278.

It is an arithmetic number, because the mean of its divisors is an integer number (3734571813).

Almost surely, 2^21340410340 is an apocalyptic number.

21340410340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21340410340 is an abundant number, since it is smaller than the sum of its proper divisors (23474451416).

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

21340410340 is a wasteful number, since it uses less digits than its factorization.

21340410340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1067020526 (or 1067020524 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 22.

Adding to 21340410340 its reverse (4301404312), we get a palindrome (25641814652).

The spelling of 21340410340 in words is "twenty-one billion, three hundred forty million, four hundred ten thousand, three hundred forty".