81447452100 has 567 divisors, whose sum is σ = 310308883101. Its totient is φ = 18493272000.

The previous prime is 81447452077. The next prime is 81447452131. The reversal of 81447452100 is 125474418.

81447452100 = 1³ + 2³ + ... + 755³.

It is a happy number.

The square root of 81447452100 is 285390.

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

81447452100 is a `hidden beast` number, since 81 + 4 + 474 + 5 + 2 + 100 = 666.

It can be written as a sum of positive squares in only one way, i.e., 29321082756 + 52126369344 = 171234^2 + 228312^2 .

It is a tau number, because it is divible by the number of its divisors (567).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 188 ways as a sum of consecutive naturals, for example, 539387025 + ... + 539387175.

Almost surely, 2^81447452100 is an apocalyptic number.

81447452100 is the 285390-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81447452100

81447452100 is an abundant number, since it is smaller than the sum of its proper divisors (228861431001).

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

81447452100 is a wasteful number, since it uses less digits than its factorization.

81447452100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 348 (or 168 counting only the distinct ones).

The product of its (nonzero) digits is 35840, while the sum is 36.

Multiplying 81447452100 by its sum of digits (36), we get a square (2932108275600 = 1712340²).

81447452100 divided by its sum of digits (36) gives a square (2262429225 = 47565²).

The spelling of 81447452100 in words is "eighty-one billion, four hundred forty-seven million, four hundred fifty-two thousand, one hundred".