378078644161 has 3 divisors (see below), whose sum is σ = 378079259043. Its totient is φ = 378078029280.

The previous prime is 378078644143. The next prime is 378078644201. The reversal of 378078644161 is 161446870873.

The square root of 378078644161 is 614881.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 161446870873 = 4217 ⋅38284769.

It can be written as a sum of positive squares in only one way, i.e., 377525453761 + 553190400 = 614431^2 + 23520^2 .

It is not a de Polignac number, because 378078644161 - 2⁷ = 378078644033 is a prime.

It is a super-2 number, since 2×378078644161² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (378078644761) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 307441 + ... + 922321.

It is an arithmetic number, because the mean of its divisors is an integer number (126026419681).

Almost surely, 2^378078644161 is an apocalyptic number.

378078644161 is the 614881-st square number.

378078644161 is the 307441-st centered octagonal number.

It is an amenable number.

378078644161 is a deficient number, since it is larger than the sum of its proper divisors (614882).

378078644161 is an frugal number, since it uses more digits than its factorization.

378078644161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1229762 (or 614881 counting only the distinct ones).

The product of its (nonzero) digits is 5419008, while the sum is 55.

The spelling of 378078644161 in words is "three hundred seventy-eight billion, seventy-eight million, six hundred forty-four thousand, one hundred sixty-one".