201978385434 has 240 divisors, whose sum is σ = 545839173792. Its totient is φ = 55615025088.

The previous prime is 201978385387. The next prime is 201978385447. The reversal of 201978385434 is 434583879102.

It is a happy number.

201978385434 is a `hidden beast` number, since 2 + 0 + 1 + 97 + 8 + 3 + 8 + 543 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 31423329 + ... + 31429755.

Almost surely, 2^201978385434 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 201978385434, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (272919586896).

201978385434 is an abundant number, since it is smaller than the sum of its proper divisors (343860788358).

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

201978385434 is a wasteful number, since it uses less digits than its factorization.

201978385434 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6599 (or 6583 counting only the distinct ones).

The product of its (nonzero) digits is 5806080, while the sum is 54.

The spelling of 201978385434 in words is "two hundred one billion, nine hundred seventy-eight million, three hundred eighty-five thousand, four hundred thirty-four".