21341240 has 32 divisors (see below), whose sum is σ = 50107680. Its totient is φ = 8164992.

The previous prime is 21341191. The next prime is 21341249. The reversal of 21341240 is 4214312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21341249) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10679 + ... + 12518.

It is an arithmetic number, because the mean of its divisors is an integer number (1565865).

Almost surely, 2^21341240 is an apocalyptic number.

21341240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21341240 is an abundant number, since it is smaller than the sum of its proper divisors (28766440).

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

21341240 is a wasteful number, since it uses less digits than its factorization.

21341240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23231 (or 23227 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 21341240 is about 4619.6579959993. The cubic root of 21341240 is about 277.3787691111.

Adding to 21341240 its reverse (4214312), we get a palindrome (25555552).

The spelling of 21341240 in words is "twenty-one million, three hundred forty-one thousand, two hundred forty".