67721005440 has 768 divisors, whose sum is σ = 264648384000. Its totient is φ = 15814656000.

The previous prime is 67721005427. The next prime is 67721005447. The reversal of 67721005440 is 4450012776.

67721005440 is a `hidden beast` number, since 6 + 7 + 7 + 2 + 100 + 544 + 0 = 666.

It is a super-2 number, since 2×67721005440² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 67721005395 and 67721005404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (67721005447) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 340306461 + ... + 340306659.

It is an arithmetic number, because the mean of its divisors is an integer number (344594250).

Almost surely, 2^67721005440 is an apocalyptic number.

67721005440 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 67721005440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (132324192000).

67721005440 is an abundant number, since it is smaller than the sum of its proper divisors (196927378560).

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

67721005440 is a wasteful number, since it uses less digits than its factorization.

67721005440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 407 (or 392 counting only the distinct ones).

The product of its (nonzero) digits is 47040, while the sum is 36.

The spelling of 67721005440 in words is "sixty-seven billion, seven hundred twenty-one million, five thousand, four hundred forty".