1987211520 has 432 divisors, whose sum is σ = 8277709440. Its totient is φ = 429981696.

The previous prime is 1987211483. The next prime is 1987211533. The reversal of 1987211520 is 251127891.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 1531512 + ... + 1532808.

Almost surely, 2^1987211520 is an apocalyptic number.

1987211520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1987211520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4138854720).

1987211520 is an abundant number, since it is smaller than the sum of its proper divisors (6290497920).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1987211520 is a wasteful number, since it uses less digits than its factorization.

1987211520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1350 (or 1333 counting only the distinct ones).

The product of its (nonzero) digits is 10080, while the sum is 36.

The square root of 1987211520 is about 44578.1507018853. The cubic root of 1987211520 is about 1257.2298932263.

The spelling of 1987211520 in words is "one billion, nine hundred eighty-seven million, two hundred eleven thousand, five hundred twenty".