21463651 has 8 divisors (see below), whose sum is σ = 23765184. Its totient is φ = 19220520.

The previous prime is 21463649. The next prime is 21463667. The reversal of 21463651 is 15636412.

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

It is not a de Polignac number, because 21463651 - 2¹ = 21463649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21463601) 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 7 ways as a sum of consecutive naturals, for example, 13825 + ... + 15298.

It is an arithmetic number, because the mean of its divisors is an integer number (2970648).

Almost surely, 2^21463651 is an apocalyptic number.

21463651 is a deficient number, since it is larger than the sum of its proper divisors (2301533).

21463651 is a wasteful number, since it uses less digits than its factorization.

21463651 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29201.

The product of its digits is 4320, while the sum is 28.

The square root of 21463651 is about 4632.8879761980. The cubic root of 21463651 is about 277.9080963571.

The spelling of 21463651 in words is "twenty-one million, four hundred sixty-three thousand, six hundred fifty-one".