211804969 has 2 divisors, whose sum is σ = 211804970. Its totient is φ = 211804968.

The previous prime is 211804939. The next prime is 211804973. The reversal of 211804969 is 969408112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 130804969 + 81000000 = 11437^2 + 9000^2 .

It is a cyclic number.

It is not a de Polignac number, because 211804969 - 2²³ = 203416361 is a prime.

It is a super-2 number, since 2×211804969² = 89722689786181922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (211804939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105902484 + 105902485.

It is an arithmetic number, because the mean of its divisors is an integer number (105902485).

Almost surely, 2^211804969 is an apocalyptic number.

It is an amenable number.

211804969 is a deficient number, since it is larger than the sum of its proper divisors (1).

211804969 is an equidigital number, since it uses as much as digits as its factorization.

211804969 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 40.

The square root of 211804969 is about 14553.5208454862. The cubic root of 211804969 is about 596.0902909991.

The spelling of 211804969 in words is "two hundred eleven million, eight hundred four thousand, nine hundred sixty-nine".