8781920640 has 128 divisors (see below), whose sum is σ = 31102696800. Its totient is φ = 2341840896.

The previous prime is 8781920629. The next prime is 8781920663. The reversal of 8781920640 is 460291878.

It is a tau number, because it is divible by the number of its divisors (128).

It is a super-3 number, since 3×8781920640³ (a number of 31 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 236827 + ... + 271386.

Almost surely, 2^8781920640 is an apocalyptic number.

8781920640 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

8781920640 is an abundant number, since it is smaller than the sum of its proper divisors (22320776160).

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

8781920640 is a wasteful number, since it uses less digits than its factorization.

8781920640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 508241 (or 508223 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 45.

The square root of 8781920640 is about 93711.9023390306. The cubic root of 8781920640 is about 2063.1454006638.

The spelling of 8781920640 in words is "eight billion, seven hundred eighty-one million, nine hundred twenty thousand, six hundred forty".