1977145 has 4 divisors (see below), whose sum is σ = 2372580. Its totient is φ = 1581712.

The previous prime is 1977139. The next prime is 1977163. The reversal of 1977145 is 5417791.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 817216 + 1159929 = 904^2 + 1077^2 .

It is a cyclic number.

It is not a de Polignac number, because 1977145 - 2⁹ = 1976633 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1977145.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 197710 + ... + 197719.

It is an arithmetic number, because the mean of its divisors is an integer number (593145).

2^1977145 is an apocalyptic number.

It is an amenable number.

1977145 is a deficient number, since it is larger than the sum of its proper divisors (395435).

1977145 is an equidigital number, since it uses as much as digits as its factorization.

1977145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 395434.

The product of its digits is 8820, while the sum is 34.

The square root of 1977145 is about 1406.1098819082. The cubic root of 1977145 is about 125.5103402537.

The spelling of 1977145 in words is "one million, nine hundred seventy-seven thousand, one hundred forty-five".