164347781 has 8 divisors (see below), whose sum is σ = 177727704. Its totient is φ = 151073280.

The previous prime is 164347769. The next prime is 164347787. The reversal of 164347781 is 187743461.

It can be written as a sum of positive squares in 4 ways, for example, as 68973025 + 95374756 = 8305^2 + 9766^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 164347781 - 2¹⁴ = 164331397 is a prime.

It is a super-2 number, since 2×164347781² = 54020386239247922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (164347787) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23096 + ... + 29361.

It is an arithmetic number, because the mean of its divisors is an integer number (22215963).

Almost surely, 2^164347781 is an apocalyptic number.

It is an amenable number.

164347781 is a deficient number, since it is larger than the sum of its proper divisors (13379923).

164347781 is a wasteful number, since it uses less digits than its factorization.

164347781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52711.

The product of its digits is 112896, while the sum is 41.

The square root of 164347781 is about 12819.8198505283. The cubic root of 164347781 is about 547.7570150579.

The spelling of 164347781 in words is "one hundred sixty-four million, three hundred forty-seven thousand, seven hundred eighty-one".