981778136 has 8 divisors (see below), whose sum is σ = 1840834020. Its totient is φ = 490889064.

The previous prime is 981778123. The next prime is 981778139. The reversal of 981778136 is 631877189.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (981778139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61361126 + ... + 61361141.

Almost surely, 2^981778136 is an apocalyptic number.

It is an amenable number.

981778136 is a deficient number, since it is larger than the sum of its proper divisors (859055884).

981778136 is a wasteful number, since it uses less digits than its factorization.

981778136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122722273 (or 122722269 counting only the distinct ones).

The product of its digits is 508032, while the sum is 50.

The square root of 981778136 is about 31333.3390496449. The cubic root of 981778136 is about 993.8887743330. Note that the first 3 decimals are identical.

The spelling of 981778136 in words is "nine hundred eighty-one million, seven hundred seventy-eight thousand, one hundred thirty-six".