115721840 has 40 divisors (see below), whose sum is σ = 289752288. Its totient is φ = 42727680.

The previous prime is 115721821. The next prime is 115721867. The reversal of 115721840 is 48127511.

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, 54596 + ... + 56675.

Almost surely, 2^115721840 is an apocalyptic number.

115721840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

115721840 is an abundant number, since it is smaller than the sum of its proper divisors (174030448).

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

115721840 is a wasteful number, since it uses less digits than its factorization.

115721840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111297 (or 111291 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 29.

The square root of 115721840 is about 10757.4086098837. The cubic root of 115721840 is about 487.3097605294.

The spelling of 115721840 in words is "one hundred fifteen million, seven hundred twenty-one thousand, eight hundred forty".