3855564778 has 16 divisors (see below), whose sum is σ = 6556021920. Its totient is φ = 1685833776.

The previous prime is 3855564763. The next prime is 3855564787. The reversal of 3855564778 is 8774655583.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3901900 + ... + 3902887.

It is an arithmetic number, because the mean of its divisors is an integer number (409751370).

Almost surely, 2^3855564778 is an apocalyptic number.

3855564778 is a gapful number since it is divisible by the number (38) formed by its first and last digit.

3855564778 is a deficient number, since it is larger than the sum of its proper divisors (2700457142).

3855564778 is a wasteful number, since it uses less digits than its factorization.

3855564778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7804821.

The product of its digits is 28224000, while the sum is 58.

The square root of 3855564778 is about 62093.1942969598. The cubic root of 3855564778 is about 1568.0599697341.

The spelling of 3855564778 in words is "three billion, eight hundred fifty-five million, five hundred sixty-four thousand, seven hundred seventy-eight".