1987949 has 4 divisors (see below), whose sum is σ = 1996860. Its totient is φ = 1979040.

The previous prime is 1987939. The next prime is 1987969. The reversal of 1987949 is 9497891.

1987949 is nontrivially palindromic in base 4.

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 1755625 + 232324 = 1325^2 + 482^2 .

It is a cyclic number.

It is not a de Polignac number, because 1987949 - 2⁸ = 1987693 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1987919) 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, 4112 + ... + 4569.

It is an arithmetic number, because the mean of its divisors is an integer number (499215).

2^1987949 is an apocalyptic number.

It is an amenable number.

1987949 is a deficient number, since it is larger than the sum of its proper divisors (8911).

1987949 is an equidigital number, since it uses as much as digits as its factorization.

1987949 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8910.

The product of its digits is 163296, while the sum is 47.

The square root of 1987949 is about 1409.9464528839. The cubic root of 1987949 is about 125.7385398771.

The spelling of 1987949 in words is "one million, nine hundred eighty-seven thousand, nine hundred forty-nine".