1240217189 has 2 divisors, whose sum is σ = 1240217190. Its totient is φ = 1240217188.

The previous prime is 1240217183. The next prime is 1240217213. The reversal of 1240217189 is 9817120421.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1209857089 + 30360100 = 34783^2 + 5510^2 .

It is an emirp because it is prime and its reverse (9817120421) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1240217189 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1240217183) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 620108594 + 620108595.

It is an arithmetic number, because the mean of its divisors is an integer number (620108595).

Almost surely, 2^1240217189 is an apocalyptic number.

It is an amenable number.

1240217189 is a deficient number, since it is larger than the sum of its proper divisors (1).

1240217189 is an equidigital number, since it uses as much as digits as its factorization.

1240217189 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8064, while the sum is 35.

The square root of 1240217189 is about 35216.7174648632. The cubic root of 1240217189 is about 1074.3997915730.

The spelling of 1240217189 in words is "one billion, two hundred forty million, two hundred seventeen thousand, one hundred eighty-nine".