164913921781 has 16 divisors (see below), whose sum is σ = 190200153600. Its totient is φ = 140060245248.

The previous prime is 164913921773. The next prime is 164913921791. The reversal of 164913921781 is 187129319461.

It is not a de Polignac number, because 164913921781 - 2³ = 164913921773 is a prime.

It is a super-2 number, since 2×164913921781² (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 (164913921721) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2649940 + ... + 2711458.

It is an arithmetic number, because the mean of its divisors is an integer number (11887509600).

Almost surely, 2^164913921781 is an apocalyptic number.

It is an amenable number.

164913921781 is a deficient number, since it is larger than the sum of its proper divisors (25286231819).

164913921781 is a wasteful number, since it uses less digits than its factorization.

164913921781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65028.

The product of its digits is 653184, while the sum is 52.

The spelling of 164913921781 in words is "one hundred sixty-four billion, nine hundred thirteen million, nine hundred twenty-one thousand, seven hundred eighty-one".