191555028900 has 189 divisors, whose sum is σ = 623611227603. Its totient is φ = 51049828800.

The previous prime is 191555028893. The next prime is 191555028901. The reversal of 191555028900 is 9820555191.

The square root of 191555028900 is 437670.

It is a perfect power (a square), and thus also a powerful number.

191555028900 is a `hidden beast` number, since 1 + 9 + 1 + 5 + 550 + 2 + 8 + 90 + 0 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 3809605284 + 187745423616 = 61722^2 + 433296^2 .

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

It is not an unprimeable number, because it can be changed into a prime (191555028901) by changing a digit.

It is a polite number, since it can be written in 62 ways as a sum of consecutive naturals, for example, 118170090 + ... + 118171710.

Almost surely, 2^191555028900 is an apocalyptic number.

191555028900 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

191555028900 is the 437670-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 191555028900

191555028900 is an abundant number, since it is smaller than the sum of its proper divisors (432056198703).

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

191555028900 is an frugal number, since it uses more digits than its factorization.

191555028900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3274 (or 1631 counting only the distinct ones).

The product of its (nonzero) digits is 162000, while the sum is 45.

The spelling of 191555028900 in words is "one hundred ninety-one billion, five hundred fifty-five million, twenty-eight thousand, nine hundred".