21403218245 has 8 divisors (see below), whose sum is σ = 26512373760. Its totient is φ = 16570233360.

The previous prime is 21403218241. The next prime is 21403218253. The reversal of 21403218245 is 54281230412.

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

It is not a de Polignac number, because 21403218245 - 2² = 21403218241 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21403218241) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 69042485 + ... + 69042794.

It is an arithmetic number, because the mean of its divisors is an integer number (3314046720).

Almost surely, 2^21403218245 is an apocalyptic number.

It is an amenable number.

21403218245 is a deficient number, since it is larger than the sum of its proper divisors (5109155515).

21403218245 is a wasteful number, since it uses less digits than its factorization.

21403218245 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138085315.

The product of its (nonzero) digits is 15360, while the sum is 32.

Adding to 21403218245 its reverse (54281230412), we get a palindrome (75684448657).

The spelling of 21403218245 in words is "twenty-one billion, four hundred three million, two hundred eighteen thousand, two hundred forty-five".