1578379949 has 4 divisors (see below), whose sum is σ = 1578923964. Its totient is φ = 1577835936.

The previous prime is 1578379937. The next prime is 1578379961. The reversal of 1578379949 is 9499738751.

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

It is an interprime number because it is at equal distance from previous prime (1578379937) and next prime (1578379961).

It can be written as a sum of positive squares in 2 ways, for example, as 1450848100 + 127531849 = 38090^2 + 11293^2 .

It is a cyclic number.

It is not a de Polignac number, because 1578379949 - 2¹² = 1578375853 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1578379891 and 1578379900.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1578379969) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 267632 + ... + 273465.

It is an arithmetic number, because the mean of its divisors is an integer number (394730991).

Almost surely, 2^1578379949 is an apocalyptic number.

It is an amenable number.

1578379949 is a deficient number, since it is larger than the sum of its proper divisors (544015).

1578379949 is an equidigital number, since it uses as much as digits as its factorization.

1578379949 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 544014.

The product of its digits is 17146080, while the sum is 62.

The square root of 1578379949 is about 39728.8301992394. The cubic root of 1578379949 is about 1164.3150692802.

The spelling of 1578379949 in words is "one billion, five hundred seventy-eight million, three hundred seventy-nine thousand, nine hundred forty-nine".