1211897760 has 96 divisors (see below), whose sum is σ = 3882271680. Its totient is φ = 317687808.

The previous prime is 1211897749. The next prime is 1211897779. The reversal of 1211897760 is 677981121.

It is a tau number, because it is divible by the number of its divisors (96).

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, 6924 + ... + 49716.

It is an arithmetic number, because the mean of its divisors is an integer number (40440330).

Almost surely, 2^1211897760 is an apocalyptic number.

1211897760 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 1211897760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1941135840).

1211897760 is an abundant number, since it is smaller than the sum of its proper divisors (2670373920).

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

1211897760 is a wasteful number, since it uses less digits than its factorization.

1211897760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42870 (or 42862 counting only the distinct ones).

The product of its (nonzero) digits is 42336, while the sum is 42.

The square root of 1211897760 is about 34812.3219564567. The cubic root of 1211897760 is about 1066.1590414463.

The spelling of 1211897760 in words is "one billion, two hundred eleven million, eight hundred ninety-seven thousand, seven hundred sixty".