1866538151 has 2 divisors, whose sum is σ = 1866538152. Its totient is φ = 1866538150.

The previous prime is 1866538147. The next prime is 1866538187. The reversal of 1866538151 is 1518356681.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1866538151 - 2² = 1866538147 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1866538111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 933269075 + 933269076.

It is an arithmetic number, because the mean of its divisors is an integer number (933269076).

Almost surely, 2^1866538151 is an apocalyptic number.

1866538151 is a deficient number, since it is larger than the sum of its proper divisors (1).

1866538151 is an equidigital number, since it uses as much as digits as its factorization.

1866538151 is an evil number, because the sum of its binary digits is even.

The product of its digits is 172800, while the sum is 44.

The square root of 1866538151 is about 43203.4506839442. The cubic root of 1866538151 is about 1231.2482428071.

The spelling of 1866538151 in words is "one billion, eight hundred sixty-six million, five hundred thirty-eight thousand, one hundred fifty-one".