1265020720 has 40 divisors (see below), whose sum is σ = 3036055680. Its totient is φ = 489684480.

The previous prime is 1265020717. The next prime is 1265020721. The reversal of 1265020720 is 270205621.

It is a tau number, because it is divible by the number of its divisors (40).

It is not an unprimeable number, because it can be changed into a prime (1265020721) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 252565 + ... + 257524.

It is an arithmetic number, because the mean of its divisors is an integer number (75901392).

Almost surely, 2^1265020720 is an apocalyptic number.

1265020720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1265020720 is an abundant number, since it is smaller than the sum of its proper divisors (1771034960).

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

1265020720 is a wasteful number, since it uses less digits than its factorization.

1265020720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 510133 (or 510127 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 25.

The square root of 1265020720 is about 35567.1297689313. The cubic root of 1265020720 is about 1081.5149977184.

The spelling of 1265020720 in words is "one billion, two hundred sixty-five million, twenty thousand, seven hundred twenty".