21047446 has 32 divisors (see below), whose sum is σ = 38154240. Its totient is φ = 8516256.

The previous prime is 21047443. The next prime is 21047449. The reversal of 21047446 is 64474012.

It is an interprime number because it is at equal distance from previous prime (21047443) and next prime (21047449).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21047441) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18531 + ... + 19633.

It is an arithmetic number, because the mean of its divisors is an integer number (1192320).

Almost surely, 2^21047446 is an apocalyptic number.

21047446 is a deficient number, since it is larger than the sum of its proper divisors (17106794).

21047446 is a wasteful number, since it uses less digits than its factorization.

21047446 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1188.

The product of its (nonzero) digits is 5376, while the sum is 28.

The square root of 21047446 is about 4587.7495572448. The cubic root of 21047446 is about 276.1000389998.

The spelling of 21047446 in words is "twenty-one million, forty-seven thousand, four hundred forty-six".