21455011234511 has 12 divisors (see below), whose sum is σ = 22792400079552. Its totient is φ = 20191985515008.

The previous prime is 21455011234493. The next prime is 21455011234519. The reversal of 21455011234511 is 11543211055412.

It is a happy number.

It is not a de Polignac number, because 21455011234511 - 2¹⁴ = 21455011218127 is a prime.

It is a hoax number, since the sum of its digits (35) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21455011234519) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4309991 + ... + 7841303.

It is an arithmetic number, because the mean of its divisors is an integer number (1899366673296).

Almost surely, 2^{21455011234511} is an apocalyptic number.

21455011234511 is a deficient number, since it is larger than the sum of its proper divisors (1337388845041).

21455011234511 is a wasteful number, since it uses less digits than its factorization.

21455011234511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3552370 (or 3552353 counting only the distinct ones).

The product of its (nonzero) digits is 24000, while the sum is 35.

Adding to 21455011234511 its reverse (11543211055412), we get a palindrome (32998222289923).

The spelling of 21455011234511 in words is "twenty-one trillion, four hundred fifty-five billion, eleven million, two hundred thirty-four thousand, five hundred eleven".