21496751 has 8 divisors (see below), whose sum is σ = 22289904. Its totient is φ = 20716480.

The previous prime is 21496723. The next prime is 21496753. The reversal of 21496751 is 15769412.

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

It is a de Polignac number, because none of the positive numbers 2^k-21496751 is a prime.

It is a super-3 number, since 3×21496751³ (a number of 23 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21496753) 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, 245 + ... + 6561.

It is an arithmetic number, because the mean of its divisors is an integer number (2786238).

Almost surely, 2^21496751 is an apocalyptic number.

21496751 is a deficient number, since it is larger than the sum of its proper divisors (793153).

21496751 is an equidigital number, since it uses as much as digits as its factorization.

21496751 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6441.

The product of its digits is 15120, while the sum is 35.

The square root of 21496751 is about 4636.4588858309. The cubic root of 21496751 is about 278.0508809100.

The spelling of 21496751 in words is "twenty-one million, four hundred ninety-six thousand, seven hundred fifty-one".