869066021 has 2 divisors, whose sum is σ = 869066022. Its totient is φ = 869066020.

The previous prime is 869065931. The next prime is 869066071. The reversal of 869066021 is 120660968.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 453477025 + 415588996 = 21295^2 + 20386^2 .

It is a cyclic number.

It is not a de Polignac number, because 869066021 - 2¹⁴ = 869049637 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (869066071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 434533010 + 434533011.

It is an arithmetic number, because the mean of its divisors is an integer number (434533011).

Almost surely, 2^869066021 is an apocalyptic number.

It is an amenable number.

869066021 is a deficient number, since it is larger than the sum of its proper divisors (1).

869066021 is an equidigital number, since it uses as much as digits as its factorization.

869066021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 31104, while the sum is 38.

The square root of 869066021 is about 29479.9257292144. The cubic root of 869066021 is about 954.2985340713.

The spelling of 869066021 in words is "eight hundred sixty-nine million, sixty-six thousand, twenty-one".