8390661240 has 128 divisors (see below), whose sum is σ = 27133263360. Its totient is φ = 2063491584.

The previous prime is 8390661197. The next prime is 8390661241. The reversal of 8390661240 is 421660938.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8390661241) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2505247 + ... + 2508593.

It is an arithmetic number, because the mean of its divisors is an integer number (211978620).

Almost surely, 2^8390661240 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 8390661240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13566631680).

8390661240 is an abundant number, since it is smaller than the sum of its proper divisors (18742602120).

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

8390661240 is a wasteful number, since it uses less digits than its factorization.

8390661240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4981 (or 4977 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 39.

The square root of 8390661240 is about 91600.5526184204. The cubic root of 8390661240 is about 2032.0391103463.

The spelling of 8390661240 in words is "eight billion, three hundred ninety million, six hundred sixty-one thousand, two hundred forty".