21373005 has 24 divisors (see below), whose sum is σ = 36100512. Its totient is φ = 10796256.

The previous prime is 21372991. The next prime is 21373061. The reversal of 21373005 is 50037312.

It is a happy number.

It is not a de Polignac number, because 21373005 - 2¹⁶ = 21307469 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3442 + ... + 7388.

It is an arithmetic number, because the mean of its divisors is an integer number (1504188).

Almost surely, 2^21373005 is an apocalyptic number.

It is an amenable number.

21373005 is a deficient number, since it is larger than the sum of its proper divisors (14727507).

21373005 is a wasteful number, since it uses less digits than its factorization.

21373005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3993 (or 3974 counting only the distinct ones).

The product of its (nonzero) digits is 630, while the sum is 21.

The square root of 21373005 is about 4623.0947427021. The cubic root of 21373005 is about 277.5163207672.

The spelling of 21373005 in words is "twenty-one million, three hundred seventy-three thousand, five".