21405133550415 has 8 divisors (see below), whose sum is σ = 34248213680688. Its totient is φ = 11416071226880.

The previous prime is 21405133550413. The next prime is 21405133550503. The reversal of 21405133550415 is 51405533150412.

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

It is not a de Polignac number, because 21405133550415 - 2¹ = 21405133550413 is a prime.

It is a super-2 number, since 2×21405133550415² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21405133550413) 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, 713504451666 + ... + 713504451695.

It is an arithmetic number, because the mean of its divisors is an integer number (4281026710086).

Almost surely, 2^{21405133550415} is an apocalyptic number.

21405133550415 is a deficient number, since it is larger than the sum of its proper divisors (12843080130273).

21405133550415 is a wasteful number, since it uses less digits than its factorization.

21405133550415 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1427008903369.

The product of its (nonzero) digits is 180000, while the sum is 39.

The spelling of 21405133550415 in words is "twenty-one trillion, four hundred five billion, one hundred thirty-three million, five hundred fifty thousand, four hundred fifteen".