30777978 has 96 divisors (see below), whose sum is σ = 80898048. Its totient is φ = 7711200.

The previous prime is 30777941. The next prime is 30778021. The reversal of 30777978 is 87977703.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 100101 + ... + 100407.

It is an arithmetic number, because the mean of its divisors is an integer number (842688).

Almost surely, 2^30777978 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 30777978, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40449024).

30777978 is an abundant number, since it is smaller than the sum of its proper divisors (50120070).

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

30777978 is a wasteful number, since it uses less digits than its factorization.

30777978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 368 (or 361 counting only the distinct ones).

The product of its (nonzero) digits is 518616, while the sum is 48.

The square root of 30777978 is about 5547.7903709495. The cubic root of 30777978 is about 313.3863154207.

The spelling of 30777978 in words is "thirty million, seven hundred seventy-seven thousand, nine hundred seventy-eight".