21440673 has 16 divisors (see below), whose sum is σ = 32365440. Its totient is φ = 14023152.

The previous prime is 21440647. The next prime is 21440677. The reversal of 21440673 is 37604412.

It is not a de Polignac number, because 21440673 - 2⁶ = 21440609 is a prime.

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

It is not an unprimeable number, because it can be changed into a prime (21440677) 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, 6061 + ... + 8922.

It is an arithmetic number, because the mean of its divisors is an integer number (2022840).

Almost surely, 2^21440673 is an apocalyptic number.

It is an amenable number.

21440673 is a deficient number, since it is larger than the sum of its proper divisors (10924767).

21440673 is a wasteful number, since it uses less digits than its factorization.

21440673 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15045 (or 15039 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 27.

The square root of 21440673 is about 4630.4074334771. The cubic root of 21440673 is about 277.8088890606.

The spelling of 21440673 in words is "twenty-one million, four hundred forty thousand, six hundred seventy-three".