200231981 has 2 divisors, whose sum is σ = 200231982. Its totient is φ = 200231980.

The previous prime is 200231963. The next prime is 200232029. The reversal of 200231981 is 189132002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 131905225 + 68326756 = 11485^2 + 8266^2 .

It is a cyclic number.

It is not a de Polignac number, because 200231981 - 2⁶ = 200231917 is a prime.

It is a super-2 number, since 2×200231981² = 80185692430368722, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 200231981.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (200231081) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100115990 + 100115991.

It is an arithmetic number, because the mean of its divisors is an integer number (100115991).

Almost surely, 2^200231981 is an apocalyptic number.

It is an amenable number.

200231981 is a deficient number, since it is larger than the sum of its proper divisors (1).

200231981 is an equidigital number, since it uses as much as digits as its factorization.

200231981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 200231981 is about 14150.3350137020. The cubic root of 200231981 is about 585.0295657982.

Adding to 200231981 its reverse (189132002), we get a palindrome (389363983).

The spelling of 200231981 in words is "two hundred million, two hundred thirty-one thousand, nine hundred eighty-one".