21421402455 has 8 divisors (see below), whose sum is σ = 34274243952. Its totient is φ = 11424747968.

The previous prime is 21421402439. The next prime is 21421402459. The reversal of 21421402455 is 55420412412.

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 21421402455 - 2⁴ = 21421402439 is a prime.

It is a super-3 number, since 3×21421402455³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21421402459) 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, 714046734 + ... + 714046763.

It is an arithmetic number, because the mean of its divisors is an integer number (4284280494).

Almost surely, 2^21421402455 is an apocalyptic number.

21421402455 is a deficient number, since it is larger than the sum of its proper divisors (12852841497).

21421402455 is a wasteful number, since it uses less digits than its factorization.

21421402455 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1428093505.

The product of its (nonzero) digits is 12800, while the sum is 30.

Adding to 21421402455 its reverse (55420412412), we get a palindrome (76841814867).

The spelling of 21421402455 in words is "twenty-one billion, four hundred twenty-one million, four hundred two thousand, four hundred fifty-five".