1211743680 has 224 divisors, whose sum is σ = 4655978496. Its totient is φ = 260653056.

The previous prime is 1211743669. The next prime is 1211743681. The reversal of 1211743680 is 863471121.

It is a tau number, because it is divible by the number of its divisors (224).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211743681) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 108937 + ... + 119543.

Almost surely, 2^1211743680 is an apocalyptic number.

1211743680 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 1211743680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2327989248).

1211743680 is an abundant number, since it is smaller than the sum of its proper divisors (3444234816).

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

1211743680 is a wasteful number, since it uses less digits than its factorization.

1211743680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10651 (or 10641 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 33.

The square root of 1211743680 is about 34810.1088765893. The cubic root of 1211743680 is about 1066.1138559109.

The spelling of 1211743680 in words is "one billion, two hundred eleven million, seven hundred forty-three thousand, six hundred eighty".