1987131829 has 2 divisors, whose sum is σ = 1987131830. Its totient is φ = 1987131828.

The previous prime is 1987131799. The next prime is 1987131863. The reversal of 1987131829 is 9281317891.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1428991204 + 558140625 = 37802^2 + 23625^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1987131829 is a prime.

It is a super-3 number, since 3×1987131829³ (a number of 29 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1987131869) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 993565914 + 993565915.

It is an arithmetic number, because the mean of its divisors is an integer number (993565915).

Almost surely, 2^1987131829 is an apocalyptic number.

It is an amenable number.

1987131829 is a deficient number, since it is larger than the sum of its proper divisors (1).

1987131829 is an equidigital number, since it uses as much as digits as its factorization.

1987131829 is an evil number, because the sum of its binary digits is even.

The product of its digits is 217728, while the sum is 49.

The square root of 1987131829 is about 44577.2568581783. The cubic root of 1987131829 is about 1257.2130872236.

The spelling of 1987131829 in words is "one billion, nine hundred eighty-seven million, one hundred thirty-one thousand, eight hundred twenty-nine".