213747481 has 2 divisors, whose sum is σ = 213747482. Its totient is φ = 213747480.

The previous prime is 213747461. The next prime is 213747491. The reversal of 213747481 is 184747312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 204747481 + 9000000 = 14309^2 + 3000^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-213747481 is a prime.

It is a super-2 number, since 2×213747481² = 91375971267690722, 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 213747481.

It is not a weakly prime, because it can be changed into another prime (213747461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106873740 + 106873741.

It is an arithmetic number, because the mean of its divisors is an integer number (106873741).

Almost surely, 2^213747481 is an apocalyptic number.

It is an amenable number.

213747481 is a deficient number, since it is larger than the sum of its proper divisors (1).

213747481 is an equidigital number, since it uses as much as digits as its factorization.

213747481 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 37632, while the sum is 37.

The square root of 213747481 is about 14620.1053689773. The cubic root of 213747481 is about 597.9070419594.

The spelling of 213747481 in words is "two hundred thirteen million, seven hundred forty-seven thousand, four hundred eighty-one".