21110340 has 48 divisors (see below), whose sum is σ = 59447808. Its totient is φ = 5597184.

The previous prime is 21110263. The next prime is 21110363. The reversal of 21110340 is 4301112.

21110340 = 230² + 231² + ... + 422².

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10669 + ... + 12491.

It is an arithmetic number, because the mean of its divisors is an integer number (1238496).

Almost surely, 2^21110340 is an apocalyptic number.

21110340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21110340 is an abundant number, since it is smaller than the sum of its proper divisors (38337468).

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

21110340 is a wasteful number, since it uses less digits than its factorization.

21110340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2028 (or 2026 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 21110340 is about 4594.5990031775. The cubic root of 21110340 is about 276.3747796622.

Adding to 21110340 its reverse (4301112), we get a palindrome (25411452).

The spelling of 21110340 in words is "twenty-one million, one hundred ten thousand, three hundred forty".