21436056 has 32 divisors (see below), whose sum is σ = 59545200. Its totient is φ = 7145280.

The previous prime is 21436027. The next prime is 21436067. The reversal of 21436056 is 65063412.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 49405 + ... + 49836.

Almost surely, 2^21436056 is an apocalyptic number.

It is an amenable number.

21436056 is an abundant number, since it is smaller than the sum of its proper divisors (38109144).

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

21436056 is a wasteful number, since it uses less digits than its factorization.

21436056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99256 (or 99246 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 21436056 is about 4629.9088543944. The cubic root of 21436056 is about 277.7889466561.

Adding to 21436056 its reverse (65063412), we get a palindrome (86499468).

The spelling of 21436056 in words is "twenty-one million, four hundred thirty-six thousand, fifty-six".