21456503651 has 8 divisors (see below), whose sum is σ = 23951446464. Its totient is φ = 19052286120.

The previous prime is 21456503633. The next prime is 21456503657. The reversal of 21456503651 is 15630565412.

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

It is a cyclic number.

It is not a de Polignac number, because 21456503651 - 2¹⁸ = 21456241507 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21456503657) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22680821 + ... + 22681766.

It is an arithmetic number, because the mean of its divisors is an integer number (2993930808).

Almost surely, 2^21456503651 is an apocalyptic number.

21456503651 is a deficient number, since it is larger than the sum of its proper divisors (2494942813).

21456503651 is a wasteful number, since it uses less digits than its factorization.

21456503651 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45362641.

The product of its (nonzero) digits is 108000, while the sum is 38.

The spelling of 21456503651 in words is "twenty-one billion, four hundred fifty-six million, five hundred three thousand, six hundred fifty-one".