1261330520 has 32 divisors (see below), whose sum is σ = 2839892400. Its totient is φ = 504194688.

The previous prime is 1261330513. The next prime is 1261330529. The reversal of 1261330520 is 250331621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1261330529) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 55022 + ... + 74498.

Almost surely, 2^1261330520 is an apocalyptic number.

1261330520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1261330520 is an abundant number, since it is smaller than the sum of its proper divisors (1578561880).

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

1261330520 is a wasteful number, since it uses less digits than its factorization.

1261330520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21107 (or 21103 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 23.

The square root of 1261330520 is about 35515.2153308973. The cubic root of 1261330520 is about 1080.4623420548.

The spelling of 1261330520 in words is "one billion, two hundred sixty-one million, three hundred thirty thousand, five hundred twenty".