1201577778 has 12 divisors (see below), whose sum is σ = 2603418558. Its totient is φ = 400525920.

The previous prime is 1201577749. The next prime is 1201577807. The reversal of 1201577778 is 8777751021.

It is a happy number.

1201577778 is a `hidden beast` number, since 1 + 2 + 0 + 1 + 577 + 7 + 78 = 666.

It is an interprime number because it is at equal distance from previous prime (1201577749) and next prime (1201577807).

It can be written as a sum of positive squares in only one way, i.e., 1175598369 + 25979409 = 34287^2 + 5097^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 33377143 + ... + 33377178.

Almost surely, 2^1201577778 is an apocalyptic number.

1201577778 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

1201577778 is an abundant number, since it is smaller than the sum of its proper divisors (1401840780).

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

1201577778 is a wasteful number, since it uses less digits than its factorization.

1201577778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66754329 (or 66754326 counting only the distinct ones).

The product of its (nonzero) digits is 192080, while the sum is 45.

The square root of 1201577778 is about 34663.7819344630. The cubic root of 1201577778 is about 1063.1240983562.

The spelling of 1201577778 in words is "one billion, two hundred one million, five hundred seventy-seven thousand, seven hundred seventy-eight".