67217221840 has 40 divisors (see below), whose sum is σ = 157713823080. Its totient is φ = 26640216576.

The previous prime is 67217221837. The next prime is 67217221843. The reversal of 67217221840 is 4812271276.

It is an interprime number because it is at equal distance from previous prime (67217221837) and next prime (67217221843).

It can be written as a sum of positive squares in 4 ways, for example, as 1971715216 + 65245506624 = 44404^2 + 255432^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 67217221793 and 67217221802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (67217221843) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3845479 + ... + 3862918.

It is an arithmetic number, because the mean of its divisors is an integer number (3942845577).

Almost surely, 2^67217221840 is an apocalyptic number.

It is an amenable number.

67217221840 is an abundant number, since it is smaller than the sum of its proper divisors (90496601240).

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

67217221840 is a wasteful number, since it uses less digits than its factorization.

67217221840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7708519 (or 7708513 counting only the distinct ones).

The product of its (nonzero) digits is 75264, while the sum is 40.

The spelling of 67217221840 in words is "sixty-seven billion, two hundred seventeen million, two hundred twenty-one thousand, eight hundred forty".