164215863981 has 24 divisors (see below), whose sum is σ = 256572257760. Its totient is φ = 100610719776.

The previous prime is 164215863967. The next prime is 164215863997. The reversal of 164215863981 is 189368512461.

It is a happy number.

164215863981 is a `hidden beast` number, since 1 + 6 + 4 + 21 + 586 + 39 + 8 + 1 = 666.

164215863981 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 164215863981 - 2¹³ = 164215855789 is a prime.

It is a super-2 number, since 2×164215863981² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (164215863961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3064971 + ... + 3118088.

It is an arithmetic number, because the mean of its divisors is an integer number (10690510740).

Almost surely, 2^164215863981 is an apocalyptic number.

It is an amenable number.

164215863981 is a deficient number, since it is larger than the sum of its proper divisors (92356393779).

164215863981 is a wasteful number, since it uses less digits than its factorization.

164215863981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6183305 (or 6183302 counting only the distinct ones).

The product of its digits is 2488320, while the sum is 54.

It can be divided in two parts, 164215 and 863981, that added together give a square (1028196 = 1014²).

The spelling of 164215863981 in words is "one hundred sixty-four billion, two hundred fifteen million, eight hundred sixty-three thousand, nine hundred eighty-one".