1951987 has 4 divisors (see below), whose sum is σ = 2036880. Its totient is φ = 1867096.

The previous prime is 1951967. The next prime is 1951993. The reversal of 1951987 is 7891591.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 1951987 - 2¹¹ = 1949939 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (1951967) 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, 42412 + ... + 42457.

It is an arithmetic number, because the mean of its divisors is an integer number (509220).

2^1951987 is an apocalyptic number.

1951987 is a deficient number, since it is larger than the sum of its proper divisors (84893).

1951987 is an equidigital number, since it uses as much as digits as its factorization.

1951987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84892.

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

The square root of 1951987 is about 1397.1352833566. The cubic root of 1951987 is about 124.9757179500.

The spelling of 1951987 in words is "one million, nine hundred fifty-one thousand, nine hundred eighty-seven".