21475630 has 32 divisors (see below), whose sum is σ = 42609888. Its totient is φ = 7728000.

The previous prime is 21475621. The next prime is 21475633. The reversal of 21475630 is 3657412.

It is a super-2 number, since 2×21475630² = 922405367793800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21475633) 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 15 ways as a sum of consecutive naturals, for example, 10144 + ... + 12076.

It is an arithmetic number, because the mean of its divisors is an integer number (1331559).

Almost surely, 2^21475630 is an apocalyptic number.

21475630 is a deficient number, since it is larger than the sum of its proper divisors (21134258).

21475630 is a wasteful number, since it uses less digits than its factorization.

21475630 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2052.

The product of its (nonzero) digits is 5040, while the sum is 28.

The square root of 21475630 is about 4634.1806179734. The cubic root of 21475630 is about 277.9597875000.

It can be divided in two parts, 2147 and 5630, that added together give a palindrome (7777).

The spelling of 21475630 in words is "twenty-one million, four hundred seventy-five thousand, six hundred thirty".