187821691456 has 189 divisors, whose sum is σ = 443822966937. Its totient is φ = 78633192960.

The previous prime is 187821691451. The next prime is 187821691457. The reversal of 187821691456 is 654196128781.

The square root of 187821691456 is 433384.

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

It can be written as a sum of positive squares in only one way, i.e., 130910817856 + 56910873600 = 361816^2 + 238560^2 .

Its product of digits (5806080) is a multiple of the sum of its prime divisors (189).

It is a self number, because there is not a number n which added to its sum of digits gives 187821691456.

It is not an unprimeable number, because it can be changed into a prime (187821691451) by changing a digit.

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 26 ways as a sum of consecutive naturals, for example, 1723134730 + ... + 1723134838.

Almost surely, 2^187821691456 is an apocalyptic number.

187821691456 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

187821691456 is the 433384-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 187821691456

187821691456 is an abundant number, since it is smaller than the sum of its proper divisors (256001275481).

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

187821691456 is an frugal number, since it uses more digits than its factorization.

187821691456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 386 (or 189 counting only the distinct ones).

The product of its digits is 5806080, while the sum is 58.

The spelling of 187821691456 in words is "one hundred eighty-seven billion, eight hundred twenty-one million, six hundred ninety-one thousand, four hundred fifty-six".