1261416663 has 24 divisors (see below), whose sum is σ = 1965578160. Its totient is φ = 774921600.

The previous prime is 1261416661. The next prime is 1261416697. The reversal of 1261416663 is 3666141621.

It is a happy number.

It is not a de Polignac number, because 1261416663 - 2¹ = 1261416661 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1261416661) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 61348 + ... + 79286.

It is an arithmetic number, because the mean of its divisors is an integer number (81899090).

Almost surely, 2^1261416663 is an apocalyptic number.

1261416663 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

1261416663 is a deficient number, since it is larger than the sum of its proper divisors (704161497).

1261416663 is a wasteful number, since it uses less digits than its factorization.

1261416663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18559 (or 18556 counting only the distinct ones).

The product of its digits is 31104, while the sum is 36.

The square root of 1261416663 is about 35516.4280720908. The cubic root of 1261416663 is about 1080.4869383435.

The spelling of 1261416663 in words is "one billion, two hundred sixty-one million, four hundred sixteen thousand, six hundred sixty-three".