1979851 has 4 divisors (see below), whose sum is σ = 1990000. Its totient is φ = 1969704.

The previous prime is 1979827. The next prime is 1979891. The reversal of 1979851 is 1589791.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1589791 = 7 ⋅227113.

It is a cyclic number.

It is not a de Polignac number, because 1979851 - 2⁷ = 1979723 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1979891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4776 + ... + 5173.

It is an arithmetic number, because the mean of its divisors is an integer number (497500).

2^1979851 is an apocalyptic number.

1979851 is a deficient number, since it is larger than the sum of its proper divisors (10149).

1979851 is an equidigital number, since it uses as much as digits as its factorization.

1979851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10148.

The product of its digits is 22680, while the sum is 40.

The square root of 1979851 is about 1407.0717821064. The cubic root of 1979851 is about 125.5675736474.

The spelling of 1979851 in words is "one million, nine hundred seventy-nine thousand, eight hundred fifty-one".