7866421920 has 240 divisors, whose sum is σ = 31728267648. Its totient is φ = 1798018560.

The previous prime is 7866421903. The next prime is 7866421949. The reversal of 7866421920 is 291246687.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (240).

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

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 47365 + ... + 134075.

Almost surely, 2^7866421920 is an apocalyptic number.

7866421920 is a gapful number since it is divisible by the number (70) 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 7866421920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15864133824).

7866421920 is an abundant number, since it is smaller than the sum of its proper divisors (23861845728).

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

7866421920 is a wasteful number, since it uses less digits than its factorization.

7866421920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86745 (or 86728 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 45.

The square root of 7866421920 is about 88692.8515721532. The cubic root of 7866421920 is about 1988.8059569238.

The spelling of 7866421920 in words is "seven billion, eight hundred sixty-six million, four hundred twenty-one thousand, nine hundred twenty".