187221609540 has 288 divisors, whose sum is σ = 678115017216. Its totient is φ = 40880885760.

The previous prime is 187221609511. The next prime is 187221609571. The reversal of 187221609540 is 45906122781.

187221609540 is a `hidden beast` number, since 1 + 87 + 2 + 21 + 6 + 0 + 9 + 540 = 666.

187221609540 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 25527714 + ... + 25535046.

It is an arithmetic number, because the mean of its divisors is an integer number (2354566032).

Almost surely, 2^187221609540 is an apocalyptic number.

187221609540 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 187221609540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (339057508608).

187221609540 is an abundant number, since it is smaller than the sum of its proper divisors (490893407676).

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

187221609540 is a wasteful number, since it uses less digits than its factorization.

187221609540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8259 (or 8254 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 45.

The spelling of 187221609540 in words is "one hundred eighty-seven billion, two hundred twenty-one million, six hundred nine thousand, five hundred forty".