63747991440 has 400 divisors, whose sum is σ = 257194967040. Its totient is φ = 14331479040.

The previous prime is 63747991427. The next prime is 63747991523. The reversal of 63747991440 is 4419974736.

63747991440 is a `hidden beast` number, since 63 + 74 + 79 + 9 + 1 + 440 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 2755441 + ... + 2778479.

Almost surely, 2^63747991440 is an apocalyptic number.

63747991440 is a gapful number since it is divisible by the number (60) 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 63747991440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (128597483520).

63747991440 is an abundant number, since it is smaller than the sum of its proper divisors (193446975600).

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

63747991440 is a wasteful number, since it uses less digits than its factorization.

63747991440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23132 (or 23117 counting only the distinct ones).

The product of its (nonzero) digits is 4572288, while the sum is 54.

The spelling of 63747991440 in words is "sixty-three billion, seven hundred forty-seven million, nine hundred ninety-one thousand, four hundred forty".