1125515820 has 192 divisors, whose sum is σ = 3724890624. Its totient is φ = 250337280.

The previous prime is 1125515813. The next prime is 1125515837. The reversal of 1125515820 is 285155211.

It is a super-2 number, since 2×1125515820² = 2533571722140544800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1998859 + ... + 1999421.

It is an arithmetic number, because the mean of its divisors is an integer number (19400472).

Almost surely, 2^1125515820 is an apocalyptic number.

1125515820 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 1125515820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1862445312).

1125515820 is an abundant number, since it is smaller than the sum of its proper divisors (2599374804).

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

1125515820 is a wasteful number, since it uses less digits than its factorization.

1125515820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 832 (or 830 counting only the distinct ones).

The product of its (nonzero) digits is 4000, while the sum is 30.

The square root of 1125515820 is about 33548.7081718507. The cubic root of 1125515820 is about 1040.2008426215.

The spelling of 1125515820 in words is "one billion, one hundred twenty-five million, five hundred fifteen thousand, eight hundred twenty".