67721888 has 48 divisors (see below), whose sum is σ = 144566856. Its totient is φ = 31042560.

The previous prime is 67721879. The next prime is 67721893. The reversal of 67721888 is 88812776.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 62283664 + 5438224 = 7892^2 + 2332^2 .

It is a super-2 number, since 2×67721888² = 9172508228569088, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 71498 + ... + 72438.

Almost surely, 2^67721888 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 67721888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (72283428).

67721888 is an abundant number, since it is smaller than the sum of its proper divisors (76844968).

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

67721888 is a wasteful number, since it uses less digits than its factorization.

67721888 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1137 (or 1129 counting only the distinct ones).

The product of its digits is 301056, while the sum is 47.

The square root of 67721888 is about 8229.3309570098. The cubic root of 67721888 is about 407.6083002198.

The spelling of 67721888 in words is "sixty-seven million, seven hundred twenty-one thousand, eight hundred eighty-eight".