820721170027 has 12 divisors (see below), whose sum is σ = 902255747400. Its totient is φ = 745993751360.

The previous prime is 820721169973. The next prime is 820721170037. The reversal of 820721170027 is 720071127028.

It is not a de Polignac number, because 820721170027 - 2¹⁹ = 820720645739 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (820721170037) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 254448 + ... + 1306210.

It is an arithmetic number, because the mean of its divisors is an integer number (75187978950).

Almost surely, 2^820721170027 is an apocalyptic number.

820721170027 is a deficient number, since it is larger than the sum of its proper divisors (81534577373).

820721170027 is a wasteful number, since it uses less digits than its factorization.

820721170027 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1058234 (or 1058223 counting only the distinct ones).

The product of its (nonzero) digits is 21952, while the sum is 37.

The spelling of 820721170027 in words is "eight hundred twenty billion, seven hundred twenty-one million, one hundred seventy thousand, twenty-seven".