1187216720 has 40 divisors (see below), whose sum is σ = 2766734376. Its totient is φ = 473776128.

The previous prime is 1187216717. The next prime is 1187216749. The reversal of 1187216720 is 276127811.

It can be written as a sum of positive squares in 4 ways, for example, as 132526144 + 1054690576 = 11512^2 + 32476^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17504 + ... + 51776.

Almost surely, 2^1187216720 is an apocalyptic number.

1187216720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1187216720 is an abundant number, since it is smaller than the sum of its proper divisors (1579517656).

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

1187216720 is a wasteful number, since it uses less digits than its factorization.

1187216720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34719 (or 34713 counting only the distinct ones).

The product of its (nonzero) digits is 9408, while the sum is 35.

The square root of 1187216720 is about 34456.0113768265. The cubic root of 1187216720 is about 1058.8716841667.

The spelling of 1187216720 in words is "one billion, one hundred eighty-seven million, two hundred sixteen thousand, seven hundred twenty".