21457446 has 16 divisors (see below), whose sum is σ = 43156800. Its totient is φ = 7112168.

The previous prime is 21457433. The next prime is 21457463. The reversal of 21457446 is 64475412.

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, 8916 + ... + 11063.

It is an arithmetic number, because the mean of its divisors is an integer number (2697300).

Almost surely, 2^21457446 is an apocalyptic number.

21457446 is an abundant number, since it is smaller than the sum of its proper divisors (21699354).

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

21457446 is a wasteful number, since it uses less digits than its factorization.

21457446 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20163.

The product of its digits is 26880, while the sum is 33.

The square root of 21457446 is about 4632.2182591065. The cubic root of 21457446 is about 277.8813133098.

It can be divided in two parts, 2145 and 7446, that added together give a triangular number (9591 = T₁₃₈).

The spelling of 21457446 in words is "twenty-one million, four hundred fifty-seven thousand, four hundred forty-six".