1263904139 has 4 divisors (see below), whose sum is σ = 1265953224. Its totient is φ = 1261855056.

The previous prime is 1263904133. The next prime is 1263904141. The reversal of 1263904139 is 9314093621.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1263904139 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1263904133) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1023617 + ... + 1024850.

It is an arithmetic number, because the mean of its divisors is an integer number (316488306).

Almost surely, 2^1263904139 is an apocalyptic number.

1263904139 is a deficient number, since it is larger than the sum of its proper divisors (2049085).

1263904139 is an equidigital number, since it uses as much as digits as its factorization.

1263904139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2049084.

The product of its (nonzero) digits is 34992, while the sum is 38.

The square root of 1263904139 is about 35551.4294930598. The cubic root of 1263904139 is about 1081.1967013321.

The spelling of 1263904139 in words is "one billion, two hundred sixty-three million, nine hundred four thousand, one hundred thirty-nine".