21526630 has 8 divisors (see below), whose sum is σ = 38747952. Its totient is φ = 8610648.

The previous prime is 21526619. The next prime is 21526633. The reversal of 21526630 is 3662512.

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

It is a zygodrome in base 9.

It is a junction number, because it is equal to n+sod(n) for n = 21526595 and 21526604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21526633) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1076322 + ... + 1076341.

It is an arithmetic number, because the mean of its divisors is an integer number (4843494).

Almost surely, 2^21526630 is an apocalyptic number.

21526630 is a deficient number, since it is larger than the sum of its proper divisors (17221322).

21526630 is a wasteful number, since it uses less digits than its factorization.

21526630 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2152670.

The product of its (nonzero) digits is 2160, while the sum is 25.

The square root of 21526630 is about 4639.6799458583. The cubic root of 21526630 is about 278.1796451143.

It can be divided in two parts, 215266 and 30, that added together give a square (215296 = 464²).

The spelling of 21526630 in words is "twenty-one million, five hundred twenty-six thousand, six hundred thirty".