378625661 has 4 divisors (see below), whose sum is σ = 390839424. Its totient is φ = 366411900.

The previous prime is 378625651. The next prime is 378625697. The reversal of 378625661 is 166526873.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-378625661 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (378625601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6106835 + ... + 6106896.

It is an arithmetic number, because the mean of its divisors is an integer number (97709856).

Almost surely, 2^378625661 is an apocalyptic number.

378625661 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

It is an amenable number.

378625661 is a deficient number, since it is larger than the sum of its proper divisors (12213763).

378625661 is a wasteful number, since it uses less digits than its factorization.

378625661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12213762.

The product of its digits is 362880, while the sum is 44.

The square root of 378625661 is about 19458.3057073323. The cubic root of 378625661 is about 723.4413831714.

The spelling of 378625661 in words is "three hundred seventy-eight million, six hundred twenty-five thousand, six hundred sixty-one".