1275115720 has 64 divisors (see below), whose sum is σ = 2913563520. Its totient is φ = 502170624.

The previous prime is 1275115717. The next prime is 1275115741. The reversal of 1275115720 is 275115721.

It is a super-2 number, since 2×1275115720² = 3251840198782236800, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1437117 + ... + 1438003.

It is an arithmetic number, because the mean of its divisors is an integer number (45524430).

Almost surely, 2^1275115720 is an apocalyptic number.

1275115720 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 1275115720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1456781760).

1275115720 is an abundant number, since it is smaller than the sum of its proper divisors (1638447800).

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

1275115720 is a wasteful number, since it uses less digits than its factorization.

1275115720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1414 (or 1410 counting only the distinct ones).

The product of its (nonzero) digits is 4900, while the sum is 31.

The square root of 1275115720 is about 35708.7625100619. The cubic root of 1275115720 is about 1084.3842471618.

Subtracting from 1275115720 its reverse (275115721), we obtain a palindrome (999999999).

The spelling of 1275115720 in words is "one billion, two hundred seventy-five million, one hundred fifteen thousand, seven hundred twenty".