1978149375 has 120 divisors (see below), whose sum is σ = 3820776960. Its totient is φ = 983016000.

The previous prime is 1978149361. The next prime is 1978149391. The reversal of 1978149375 is 5739418791.

It is a happy number.

1978149375 is a `hidden beast` number, since 1 + 9 + 7 + 81 + 493 + 75 = 666.

It is not a de Polignac number, because 1978149375 - 2⁵ = 1978149343 is a prime.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 8870514 + ... + 8870736.

It is an arithmetic number, because the mean of its divisors is an integer number (31839808).

Almost surely, 2^1978149375 is an apocalyptic number.

1978149375 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1978149375 is a deficient number, since it is larger than the sum of its proper divisors (1842627585).

1978149375 is a wasteful number, since it uses less digits than its factorization.

1978149375 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 351 (or 333 counting only the distinct ones).

The product of its digits is 1905120, while the sum is 54.

The square root of 1978149375 is about 44476.3912092697. The cubic root of 1978149375 is about 1255.3158943005.

The spelling of 1978149375 in words is "one billion, nine hundred seventy-eight million, one hundred forty-nine thousand, three hundred seventy-five".