2158531547 has 2 divisors, whose sum is σ = 2158531548. Its totient is φ = 2158531546.

The previous prime is 2158531511. The next prime is 2158531621. The reversal of 2158531547 is 7451358512.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2158531547 - 2⁶ = 2158531483 is a prime.

It is not a weakly prime, because it can be changed into another prime (2158531747) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1079265773 + 1079265774.

It is an arithmetic number, because the mean of its divisors is an integer number (1079265774).

Almost surely, 2^2158531547 is an apocalyptic number.

2158531547 is a deficient number, since it is larger than the sum of its proper divisors (1).

2158531547 is an equidigital number, since it uses as much as digits as its factorization.

2158531547 is an evil number, because the sum of its binary digits is even.

The product of its digits is 168000, while the sum is 41.

The square root of 2158531547 is about 46459.9994296169. Note that the first 3 decimals coincide. The cubic root of 2158531547 is about 1292.3678137147.

The spelling of 2158531547 in words is "two billion, one hundred fifty-eight million, five hundred thirty-one thousand, five hundred forty-seven".