21545533423413 has 6 divisors (see below), whose sum is σ = 31121326056054. Its totient is φ = 14363688948936.

The previous prime is 21545533423373. The next prime is 21545533423451. The reversal of 21545533423413 is 31432433554512.

21545533423413 is a `hidden beast` number, since 2 + 1 + 5 + 4 + 553 + 34 + 23 + 41 + 3 = 666.

It can be written as a sum of positive squares in only one way, i.e., 13323361413924 + 8222172009489 = 3650118^2 + 2867433^2 .

It is not a de Polignac number, because 21545533423413 - 2⁸ = 21545533423157 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21545533423613) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1196974079070 + ... + 1196974079087.

It is an arithmetic number, because the mean of its divisors is an integer number (5186887676009).

Almost surely, 2^{21545533423413} is an apocalyptic number.

It is an amenable number.

21545533423413 is a deficient number, since it is larger than the sum of its proper divisors (9575792632641).

21545533423413 is a wasteful number, since it uses less digits than its factorization.

21545533423413 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2393948158163 (or 2393948158160 counting only the distinct ones).

The product of its digits is 2592000, while the sum is 45.

Adding to 21545533423413 its reverse (31432433554512), we get a palindrome (52977966977925).

The spelling of 21545533423413 in words is "twenty-one trillion, five hundred forty-five billion, five hundred thirty-three million, four hundred twenty-three thousand, four hundred thirteen".