87997201920 has 480 divisors, whose sum is σ = 322878441600. Its totient is φ = 22086991872.

The previous prime is 87997201913. The next prime is 87997201921. The reversal of 87997201920 is 2910279978.

It is a tau number, because it is divible by the number of its divisors (480).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87997201921) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 78358479 + ... + 78359601.

It is an arithmetic number, because the mean of its divisors is an integer number (672663420).

Almost surely, 2^87997201920 is an apocalyptic number.

87997201920 is a gapful number since it is divisible by the number (80) 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 87997201920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (161439220800).

87997201920 is an abundant number, since it is smaller than the sum of its proper divisors (234881239680).

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

87997201920 is a wasteful number, since it uses less digits than its factorization.

87997201920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1350 (or 1331 counting only the distinct ones).

The product of its (nonzero) digits is 1143072, while the sum is 54.

The spelling of 87997201920 in words is "eighty-seven billion, nine hundred ninety-seven million, two hundred one thousand, nine hundred twenty".