1261544089 has 8 divisors (see below), whose sum is σ = 1417655232. Its totient is φ = 1113871440.

The previous prime is 1261544057. The next prime is 1261544149. The reversal of 1261544089 is 9804451621.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1261544089 - 2⁵ = 1261544057 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1261541089) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2109307 + ... + 2109904.

It is an arithmetic number, because the mean of its divisors is an integer number (177206904).

Almost surely, 2^1261544089 is an apocalyptic number.

It is an amenable number.

1261544089 is a deficient number, since it is larger than the sum of its proper divisors (156111143).

1261544089 is a wasteful number, since it uses less digits than its factorization.

1261544089 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4219247.

The product of its (nonzero) digits is 69120, while the sum is 40.

The square root of 1261544089 is about 35518.2219290324. The cubic root of 1261544089 is about 1080.5233200554.

The spelling of 1261544089 in words is "one billion, two hundred sixty-one million, five hundred forty-four thousand, eighty-nine".