21478632 has 32 divisors (see below), whose sum is σ = 61368000. Its totient is φ = 6136704.

The previous prime is 21478631. The next prime is 21478651. The reversal of 21478632 is 23687412.

It is a super-2 number, since 2×21478632² = 922663265182848, which contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 21478593 and 21478602.

It is not an unprimeable number, because it can be changed into a prime (21478631) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 63757 + ... + 64092.

It is an arithmetic number, because the mean of its divisors is an integer number (1917750).

Almost surely, 2^21478632 is an apocalyptic number.

It is an amenable number.

21478632 is an abundant number, since it is smaller than the sum of its proper divisors (39889368).

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

21478632 is a wasteful number, since it uses less digits than its factorization.

21478632 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 127865 (or 127861 counting only the distinct ones).

The product of its digits is 16128, while the sum is 33.

The square root of 21478632 is about 4634.5045042593. The cubic root of 21478632 is about 277.9727385582.

The spelling of 21478632 in words is "twenty-one million, four hundred seventy-eight thousand, six hundred thirty-two".