1210865880 has 128 divisors (see below), whose sum is σ = 4163143680. Its totient is φ = 275996160.

The previous prime is 1210865867. The next prime is 1210865893. The reversal of 1210865880 is 885680121.

It is an interprime number because it is at equal distance from previous prime (1210865867) and next prime (1210865893).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 331665 + ... + 335295.

It is an arithmetic number, because the mean of its divisors is an integer number (32524560).

Almost surely, 2^1210865880 is an apocalyptic number.

1210865880 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 1210865880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2081571840).

1210865880 is an abundant number, since it is smaller than the sum of its proper divisors (2952277800).

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

1210865880 is a wasteful number, since it uses less digits than its factorization.

1210865880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4049 (or 4045 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 39.

The square root of 1210865880 is about 34797.4981859329. The cubic root of 1210865880 is about 1065.8563589871.

The spelling of 1210865880 in words is "one billion, two hundred ten million, eight hundred sixty-five thousand, eight hundred eighty".