21326590 has 8 divisors (see below), whose sum is σ = 38387880. Its totient is φ = 8530632.

The previous prime is 21326587. The next prime is 21326593. The reversal of 21326590 is 9562312.

It is an interprime number because it is at equal distance from previous prime (21326587) and next prime (21326593).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21326593) 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, 1066320 + ... + 1066339.

It is an arithmetic number, because the mean of its divisors is an integer number (4798485).

Almost surely, 2^21326590 is an apocalyptic number.

21326590 is a deficient number, since it is larger than the sum of its proper divisors (17061290).

21326590 is a wasteful number, since it uses less digits than its factorization.

21326590 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2132666.

The product of its (nonzero) digits is 3240, while the sum is 28.

The square root of 21326590 is about 4618.0721085752. The cubic root of 21326590 is about 277.3152843720.

The spelling of 21326590 in words is "twenty-one million, three hundred twenty-six thousand, five hundred ninety".