21256042163436 has 24 divisors (see below), whose sum is σ = 55108257461040. Its totient is φ = 7085347387776.

The previous prime is 21256042163431. The next prime is 21256042163441. The reversal of 21256042163436 is 63436124065212.

21256042163436 is a `hidden beast` number, since 2 + 1 + 2 + 5 + 6 + 0 + 4 + 2 + 1 + 634 + 3 + 6 = 666.

It is an interprime number because it is at equal distance from previous prime (21256042163431) and next prime (21256042163441).

It is a junction number, because it is equal to n+sod(n) for n = 21256042163391 and 21256042163400.

It is not an unprimeable number, because it can be changed into a prime (21256042163431) 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, 98407602501 + ... + 98407602716.

It is an arithmetic number, because the mean of its divisors is an integer number (2296177394210).

Almost surely, 2^{21256042163436} is an apocalyptic number.

It is an amenable number.

21256042163436 is an abundant number, since it is smaller than the sum of its proper divisors (33852215297604).

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

21256042163436 is a wasteful number, since it uses less digits than its factorization.

21256042163436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 196815205230 (or 196815205222 counting only the distinct ones).

The product of its (nonzero) digits is 1244160, while the sum is 45.

The spelling of 21256042163436 in words is "twenty-one trillion, two hundred fifty-six billion, forty-two million, one hundred sixty-three thousand, four hundred thirty-six".