21298037 has 4 divisors (see below), whose sum is σ = 21315756. Its totient is φ = 21280320.

The previous prime is 21298033. The next prime is 21298073. The reversal of 21298037 is 73089212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 11115556 + 10182481 = 3334^2 + 3191^2 .

It is a cyclic number.

It is not a de Polignac number, because 21298037 - 2² = 21298033 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21297994 and 21298012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21298033) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6914 + ... + 9507.

It is an arithmetic number, because the mean of its divisors is an integer number (5328939).

Almost surely, 2^21298037 is an apocalyptic number.

It is an amenable number.

21298037 is a deficient number, since it is larger than the sum of its proper divisors (17719).

21298037 is a wasteful number, since it uses less digits than its factorization.

21298037 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17718.

The product of its (nonzero) digits is 6048, while the sum is 32.

The square root of 21298037 is about 4614.9796315910. The cubic root of 21298037 is about 277.1914683645.

The spelling of 21298037 in words is "twenty-one million, two hundred ninety-eight thousand, thirty-seven".