1243540087 has 2 divisors, whose sum is σ = 1243540088. Its totient is φ = 1243540086.

The previous prime is 1243540069. The next prime is 1243540153. The reversal of 1243540087 is 7800453421.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1243540087 - 2¹⁵ = 1243507319 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1243540037) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 621770043 + 621770044.

It is an arithmetic number, because the mean of its divisors is an integer number (621770044).

Almost surely, 2^1243540087 is an apocalyptic number.

1243540087 is a deficient number, since it is larger than the sum of its proper divisors (1).

1243540087 is an equidigital number, since it uses as much as digits as its factorization.

1243540087 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 26880, while the sum is 34.

The square root of 1243540087 is about 35263.8637559755. The cubic root of 1243540087 is about 1075.3584777418.

The spelling of 1243540087 in words is "one billion, two hundred forty-three million, five hundred forty thousand, eighty-seven".