1265620520 has 64 divisors (see below), whose sum is σ = 2960133120. Its totient is φ = 486584064.

The previous prime is 1265620519. The next prime is 1265620547. The reversal of 1265620520 is 250265621.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 117689 + ... + 127991.

It is an arithmetic number, because the mean of its divisors is an integer number (46252080).

Almost surely, 2^1265620520 is an apocalyptic number.

1265620520 is a gapful number since it is divisible by the number (10) 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 1265620520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1480066560).

1265620520 is an abundant number, since it is smaller than the sum of its proper divisors (1694512600).

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

1265620520 is a wasteful number, since it uses less digits than its factorization.

1265620520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10434 (or 10430 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 29.

The square root of 1265620520 is about 35575.5607123767. The cubic root of 1265620520 is about 1081.6859014272.

The spelling of 1265620520 in words is "one billion, two hundred sixty-five million, six hundred twenty thousand, five hundred twenty".