166277813 has 4 divisors (see below), whose sum is σ = 179068428. Its totient is φ = 153487200.

The previous prime is 166277809. The next prime is 166277819. The reversal of 166277813 is 318772661.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 81306289 + 84971524 = 9017^2 + 9218^2 .

It is a cyclic number.

It is not a de Polignac number, because 166277813 - 2² = 166277809 is a prime.

It is a super-2 number, since 2×166277813² = 55296622192125938, 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 (166277819) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6395288 + ... + 6395313.

It is an arithmetic number, because the mean of its divisors is an integer number (44767107).

Almost surely, 2^166277813 is an apocalyptic number.

166277813 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

166277813 is a deficient number, since it is larger than the sum of its proper divisors (12790615).

166277813 is a wasteful number, since it uses less digits than its factorization.

166277813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12790614.

The product of its digits is 84672, while the sum is 41.

The square root of 166277813 is about 12894.8754550015. The cubic root of 166277813 is about 549.8928860277.

The spelling of 166277813 in words is "one hundred sixty-six million, two hundred seventy-seven thousand, eight hundred thirteen".