84509978436 has 81 divisors (see below), whose sum is σ = 231381061821. Its totient is φ = 25996093344.

The previous prime is 84509978429. The next prime is 84509978453. The reversal of 84509978436 is 63487990548.

The square root of 84509978436 is 290706.

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

84509978436 is a `hidden beast` number, since 8 + 4 + 509 + 97 + 8 + 4 + 36 = 666.

It can be written as a sum of positive squares in only one way, i.e., 12501476100 + 72008502336 = 111810^2 + 268344^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 22673205 + ... + 22676931.

Almost surely, 2^84509978436 is an apocalyptic number.

84509978436 is the 290706-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 84509978436

84509978436 is an abundant number, since it is smaller than the sum of its proper divisors (146871083385).

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

84509978436 is a wasteful number, since it uses less digits than its factorization.

84509978436 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7490 (or 3745 counting only the distinct ones).

The product of its (nonzero) digits is 52254720, while the sum is 63.

The spelling of 84509978436 in words is "eighty-four billion, five hundred nine million, nine hundred seventy-eight thousand, four hundred thirty-six".