73221408 has 240 divisors, whose sum is σ = 242045496. Its totient is φ = 21565440.

The previous prime is 73221403. The next prime is 73221413. The reversal of 73221408 is 80412237.

It is an interprime number because it is at equal distance from previous prime (73221403) and next prime (73221413).

It can be written as a sum of positive squares in 4 ways, for example, as 38787984 + 34433424 = 6228^2 + 5868^2 .

It is a super-2 number, since 2×73221408² = 10722749179004928, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a zygodrome in base 6.

It is not an unprimeable number, because it can be changed into a prime (73221403) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1381510 + ... + 1381562.

Almost surely, 2^73221408 is an apocalyptic number.

73221408 is a gapful number since it is divisible by the number (78) 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 73221408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (121022748).

73221408 is an abundant number, since it is smaller than the sum of its proper divisors (168824088).

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

73221408 is a wasteful number, since it uses less digits than its factorization.

73221408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129 (or 112 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 73221408 is about 8556.9508588048. The cubic root of 73221408 is about 418.3560224657.

The spelling of 73221408 in words is "seventy-three million, two hundred twenty-one thousand, four hundred eight".