213020861 has 2 divisors, whose sum is σ = 213020862. Its totient is φ = 213020860.

The previous prime is 213020851. The next prime is 213020879. The reversal of 213020861 is 168020312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 159643225 + 53377636 = 12635^2 + 7306^2 .

It is a cyclic number.

It is not a de Polignac number, because 213020861 - 2¹⁰ = 213019837 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (213020851) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106510430 + 106510431.

It is an arithmetic number, because the mean of its divisors is an integer number (106510431).

Almost surely, 2^213020861 is an apocalyptic number.

It is an amenable number.

213020861 is a deficient number, since it is larger than the sum of its proper divisors (1).

213020861 is an equidigital number, since it uses as much as digits as its factorization.

213020861 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 213020861 is about 14595.2341879122. The cubic root of 213020861 is about 597.2287580323.

The spelling of 213020861 in words is "two hundred thirteen million, twenty thousand, eight hundred sixty-one".