21394044 has 60 divisors (see below), whose sum is σ = 63924784. Its totient is φ = 6111936.

The previous prime is 21393989. The next prime is 21394063. The reversal of 21394044 is 44049312.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 21393999 and 21394017.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 2449 + ... + 6984.

Almost surely, 2^21394044 is an apocalyptic number.

It is an amenable number.

21394044 is an abundant number, since it is smaller than the sum of its proper divisors (42530740).

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

21394044 is a wasteful number, since it uses less digits than its factorization.

21394044 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9456 (or 9445 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 21394044 is about 4625.3696068531. The cubic root of 21394044 is about 277.6073507232.

The spelling of 21394044 in words is "twenty-one million, three hundred ninety-four thousand, forty-four".