1261115604 has 72 divisors (see below), whose sum is σ = 3652183808. Its totient is φ = 359432640.

The previous prime is 1261115591. The next prime is 1261115629. The reversal of 1261115604 is 4065111621.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 100149 + ... + 112035.

Almost surely, 2^1261115604 is an apocalyptic number.

1261115604 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1261115604, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1826091904).

1261115604 is an abundant number, since it is smaller than the sum of its proper divisors (2391068204).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1261115604 is a wasteful number, since it uses less digits than its factorization.

1261115604 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12325 (or 12320 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

The square root of 1261115604 is about 35512.1895128982. The cubic root of 1261115604 is about 1080.4009725114.

The spelling of 1261115604 in words is "one billion, two hundred sixty-one million, one hundred fifteen thousand, six hundred four".