6397999650 has 240 divisors, whose sum is σ = 20488022016. Its totient is φ = 1450068480.

The previous prime is 6397999649. The next prime is 6397999651. The reversal of 6397999650 is 569997936.

It is an interprime number because it is at equal distance from previous prime (6397999649) and next prime (6397999651).

It is a Smith number, since the sum of its digits (63) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is not an unprimeable number, because it can be changed into a prime (6397999651) by changing a digit.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 3599562 + ... + 3601338.

Almost surely, 2^6397999650 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6397999650, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10244011008).

6397999650 is an abundant number, since it is smaller than the sum of its proper divisors (14090022366).

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

6397999650 is a wasteful number, since it uses less digits than its factorization.

6397999650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1935 (or 1921 counting only the distinct ones).

The product of its (nonzero) digits is 24800580, while the sum is 63.

The square root of 6397999650 is about 79987.4968354430. The cubic root of 6397999650 is about 1856.4420799091.

The spelling of 6397999650 in words is "six billion, three hundred ninety-seven million, nine hundred ninety-nine thousand, six hundred fifty".