47931209 has 2 divisors, whose sum is σ = 47931210. Its totient is φ = 47931208.

The previous prime is 47931203. The next prime is 47931223. The reversal of 47931209 is 90213974.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 30525625 + 17405584 = 5525^2 + 4172^2 .

It is a cyclic number.

It is not a de Polignac number, because 47931209 - 2⁴ = 47931193 is a prime.

It is not a weakly prime, because it can be changed into another prime (47931203) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 23965604 + 23965605.

It is an arithmetic number, because the mean of its divisors is an integer number (23965605).

Almost surely, 2^47931209 is an apocalyptic number.

It is an amenable number.

47931209 is a deficient number, since it is larger than the sum of its proper divisors (1).

47931209 is an equidigital number, since it uses as much as digits as its factorization.

47931209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13608, while the sum is 35.

The square root of 47931209 is about 6923.2368874682. The cubic root of 47931209 is about 363.2504223089.

The spelling of 47931209 in words is "forty-seven million, nine hundred thirty-one thousand, two hundred nine".