21930726 has 8 divisors (see below), whose sum is σ = 43861464. Its totient is φ = 7310240.

The previous prime is 21930721. The next prime is 21930737. The reversal of 21930726 is 62703912.

It is a sphenic number, since it is the product of 3 distinct primes.

21930726 is an admirable number.

It is a junction number, because it is equal to n+sod(n) for n = 21930693 and 21930702.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21930721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1827555 + ... + 1827566.

It is an arithmetic number, because the mean of its divisors is an integer number (5482683).

Almost surely, 2^21930726 is an apocalyptic number.

21930726 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21930726 is a wasteful number, since it uses less digits than its factorization.

21930726 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3655126.

The product of its (nonzero) digits is 4536, while the sum is 30.

The square root of 21930726 is about 4683.0253042238. The cubic root of 21930726 is about 279.9095200850.

The spelling of 21930726 in words is "twenty-one million, nine hundred thirty thousand, seven hundred twenty-six".