811220667 has 4 divisors (see below), whose sum is σ = 1081627560. Its totient is φ = 540813776.

The previous prime is 811220651. The next prime is 811220681. The reversal of 811220667 is 766022118.

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

It is a cyclic number.

It is not a de Polignac number, because 811220667 - 2⁴ = 811220651 is a prime.

It is not an unprimeable number, because it can be changed into a prime (811220167) 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 3 ways as a sum of consecutive naturals, for example, 135203442 + ... + 135203447.

It is an arithmetic number, because the mean of its divisors is an integer number (270406890).

Almost surely, 2^811220667 is an apocalyptic number.

811220667 is a deficient number, since it is larger than the sum of its proper divisors (270406893).

811220667 is a wasteful number, since it uses less digits than its factorization.

811220667 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 270406892.

The product of its (nonzero) digits is 8064, while the sum is 33.

The square root of 811220667 is about 28481.9358014865. The cubic root of 811220667 is about 932.6377755493.

It can be divided in two parts, 8112 and 20667, that multiplied together give a square (167650704 = 12948²).

The spelling of 811220667 in words is "eight hundred eleven million, two hundred twenty thousand, six hundred sixty-seven".