21451240315 has 8 divisors (see below), whose sum is σ = 25746732000. Its totient is φ = 17157496512.

The previous prime is 21451240309. The next prime is 21451240333. The reversal of 21451240315 is 51304215412.

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 21451240315 - 2²³ = 21442851707 is a prime.

It is a super-2 number, since 2×21451240315² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 409815 + ... + 459184.

It is an arithmetic number, because the mean of its divisors is an integer number (3218341500).

Almost surely, 2^21451240315 is an apocalyptic number.

21451240315 is a deficient number, since it is larger than the sum of its proper divisors (4295491685).

21451240315 is an equidigital number, since it uses as much as digits as its factorization.

21451240315 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 873941.

The product of its (nonzero) digits is 4800, while the sum is 28.

Adding to 21451240315 its reverse (51304215412), we get a palindrome (72755455727).

The spelling of 21451240315 in words is "twenty-one billion, four hundred fifty-one million, two hundred forty thousand, three hundred fifteen".