853156021 has 2 divisors, whose sum is σ = 853156022. Its totient is φ = 853156020.

The previous prime is 853156019. The next prime is 853156063. The reversal of 853156021 is 120651358.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 779023921 + 74132100 = 27911^2 + 8610^2 .

It is a cyclic number.

It is not a de Polignac number, because 853156021 - 2¹ = 853156019 is a prime.

Together with 853156019, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (853156081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 426578010 + 426578011.

It is an arithmetic number, because the mean of its divisors is an integer number (426578011).

Almost surely, 2^853156021 is an apocalyptic number.

It is an amenable number.

853156021 is a deficient number, since it is larger than the sum of its proper divisors (1).

853156021 is an equidigital number, since it uses as much as digits as its factorization.

853156021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7200, while the sum is 31.

The square root of 853156021 is about 29208.8346395401. The cubic root of 853156021 is about 948.4391807037.

The spelling of 853156021 in words is "eight hundred fifty-three million, one hundred fifty-six thousand, twenty-one".