201978378363672 has 80 divisors (see below), whose sum is σ = 599004504493560. Its totient is φ = 63365765757696.

The previous prime is 201978378363631. The next prime is 201978378363683. The reversal of 201978378363672 is 276363873879102.

It is a happy number.

201978378363672 is a `hidden beast` number, since 2 + 0 + 1 + 97 + 83 + 78 + 36 + 367 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a self number, because there is not a number n which added to its sum of digits gives 201978378363672.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 9167489818 + ... + 9167511849.

Almost surely, 2^{201978378363672} is an apocalyptic number.

It is an amenable number.

201978378363672 is an abundant number, since it is smaller than the sum of its proper divisors (397026126129888).

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

201978378363672 is a wasteful number, since it uses less digits than its factorization.

201978378363672 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18335001702 (or 18335001689 counting only the distinct ones).

The product of its (nonzero) digits is 768144384, while the sum is 72.

The spelling of 201978378363672 in words is "two hundred one trillion, nine hundred seventy-eight billion, three hundred seventy-eight million, three hundred sixty-three thousand, six hundred seventy-two".