210137381 has 2 divisors, whose sum is σ = 210137382. Its totient is φ = 210137380.

The previous prime is 210137303. The next prime is 210137387. The reversal of 210137381 is 183731012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 197852356 + 12285025 = 14066^2 + 3505^2 .

It is a cyclic number.

It is not a de Polignac number, because 210137381 - 2²² = 205943077 is a prime.

It is a super-2 number, since 2×210137381² = 88315437787078322, 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 210137381.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (210137387) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105068690 + 105068691.

It is an arithmetic number, because the mean of its divisors is an integer number (105068691).

Almost surely, 2^210137381 is an apocalyptic number.

It is an amenable number.

210137381 is a deficient number, since it is larger than the sum of its proper divisors (1).

210137381 is an equidigital number, since it uses as much as digits as its factorization.

210137381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1008, while the sum is 26.

The square root of 210137381 is about 14496.1160660364. The cubic root of 210137381 is about 594.5217832031.

Adding to 210137381 its reverse (183731012), we get a palindrome (393868393).

The spelling of 210137381 in words is "two hundred ten million, one hundred thirty-seven thousand, three hundred eighty-one".