21460340 has 24 divisors (see below), whose sum is σ = 49164192. Its totient is φ = 7803680.

The previous prime is 21460331. The next prime is 21460363. The reversal of 21460340 is 4306412.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 48554 + ... + 48993.

It is an arithmetic number, because the mean of its divisors is an integer number (2048508).

Almost surely, 2^21460340 is an apocalyptic number.

21460340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21460340 is an abundant number, since it is smaller than the sum of its proper divisors (27703852).

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

21460340 is a wasteful number, since it uses less digits than its factorization.

21460340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97567 (or 97565 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 20.

The square root of 21460340 is about 4632.5306259106. The cubic root of 21460340 is about 277.8938055137.

Adding to 21460340 its reverse (4306412), we get a palindrome (25766752).

The spelling of 21460340 in words is "twenty-one million, four hundred sixty thousand, three hundred forty".