981778806450 has 162 divisors, whose sum is σ = 2857016274021. Its totient is φ = 241601368320.

The previous prime is 981778806431. The next prime is 981778806527. The reversal of 981778806450 is 54608877189.

981778806450 is a `hidden beast` number, since 9 + 8 + 177 + 8 + 8 + 0 + 6 + 450 = 666.

It can be written as a sum of positive squares in 14 ways, for example, as 426057758361 + 555721048089 = 652731^2 + 745467^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=700635.

It is an unprimeable number.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 273245854 + ... + 273249446.

Almost surely, 2^981778806450 is an apocalyptic number.

981778806450 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 981778806450

981778806450 is an abundant number, since it is smaller than the sum of its proper divisors (1875237467571).

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

981778806450 is a wasteful number, since it uses less digits than its factorization.

With its predecessor (981778806449) it forms a Ruth-Aaron pair, since the sum of their prime factors is the same (7230).

981778806450 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7230 (or 3616 counting only the distinct ones).

The product of its (nonzero) digits is 27095040, while the sum is 63.

The spelling of 981778806450 in words is "nine hundred eighty-one billion, seven hundred seventy-eight million, eight hundred six thousand, four hundred fifty".