1638264960 has 256 divisors, whose sum is σ = 5860512000. Its totient is φ = 432488448.

The previous prime is 1638264923. The next prime is 1638264961. The reversal of 1638264960 is 694628361.

1638264960 is a `hidden beast` number, since 1 + 638 + 2 + 6 + 4 + 9 + 6 + 0 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1638264961) 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, 1952221 + ... + 1953059.

It is an arithmetic number, because the mean of its divisors is an integer number (22892625).

Almost surely, 2^1638264960 is an apocalyptic number.

1638264960 is a gapful number since it is divisible by the number (10) 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 1638264960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2930256000).

1638264960 is an abundant number, since it is smaller than the sum of its proper divisors (4222247040).

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

1638264960 is a wasteful number, since it uses less digits than its factorization.

1638264960 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 980 (or 962 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 45.

The square root of 1638264960 is about 40475.4859143161. The cubic root of 1638264960 is about 1178.8576898981.

The spelling of 1638264960 in words is "one billion, six hundred thirty-eight million, two hundred sixty-four thousand, nine hundred sixty".