21594740 has 24 divisors (see below), whose sum is σ = 45777312. Its totient is φ = 8556320.

The previous prime is 21594733. The next prime is 21594751. The reversal of 21594740 is 4749512.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21594697 and 21594706.

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, 2906 + ... + 7185.

It is an arithmetic number, because the mean of its divisors is an integer number (1907388).

Almost surely, 2^21594740 is an apocalyptic number.

21594740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21594740 is an abundant number, since it is smaller than the sum of its proper divisors (24182572).

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

21594740 is a wasteful number, since it uses less digits than its factorization.

21594740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10207 (or 10205 counting only the distinct ones).

The product of its (nonzero) digits is 10080, while the sum is 32.

The square root of 21594740 is about 4647.0140950938. The cubic root of 21594740 is about 278.4727219248.

The spelling of 21594740 in words is "twenty-one million, five hundred ninety-four thousand, seven hundred forty".