21155016131406 has 16 divisors (see below), whose sum is σ = 47011146958800. Its totient is φ = 7051672043784.

The previous prime is 21155016131401. The next prime is 21155016131411. The reversal of 21155016131406 is 60413161055112.

21155016131406 is a `hidden beast` number, since 2 + 1 + 1 + 5 + 501 + 6 + 1 + 3 + 140 + 6 = 666.

It is an interprime number because it is at equal distance from previous prime (21155016131401) and next prime (21155016131411).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21155016131401) 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, 195879778941 + ... + 195879779048.

It is an arithmetic number, because the mean of its divisors is an integer number (2938196684925).

Almost surely, 2^{21155016131406} is an apocalyptic number.

21155016131406 is an abundant number, since it is smaller than the sum of its proper divisors (25856130827394).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21155016131406 is a wasteful number, since it uses less digits than its factorization.

21155016131406 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 391759558000 (or 391759557994 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 36.

Adding to 21155016131406 its reverse (60413161055112), we get a palindrome (81568177186518).

The spelling of 21155016131406 in words is "twenty-one trillion, one hundred fifty-five billion, sixteen million, one hundred thirty-one thousand, four hundred six".