378991684 has 6 divisors (see below), whose sum is σ = 663235454. Its totient is φ = 189495840.

The previous prime is 378991649. The next prime is 378991687. The reversal of 378991684 is 486199873.

It can be written as a sum of positive squares in only one way, i.e., 201356100 + 177635584 = 14190^2 + 13328^2 .

It is not an unprimeable number, because it can be changed into a prime (378991687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 47373957 + ... + 47373964.

Almost surely, 2^378991684 is an apocalyptic number.

It is an amenable number.

378991684 is a deficient number, since it is larger than the sum of its proper divisors (284243770).

378991684 is a wasteful number, since it uses less digits than its factorization.

378991684 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94747925 (or 94747923 counting only the distinct ones).

The product of its digits is 2612736, while the sum is 55.

The square root of 378991684 is about 19467.7087506465. The cubic root of 378991684 is about 723.6744285695.

The spelling of 378991684 in words is "three hundred seventy-eight million, nine hundred ninety-one thousand, six hundred eighty-four".