30661440 has 168 divisors, whose sum is σ = 105034080. Its totient is φ = 7557120.

The previous prime is 30661403. The next prime is 30661457. The reversal of 30661440 is 4416603.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 30661440.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 747820 + ... + 747860.

Almost surely, 2^30661440 is an apocalyptic number.

30661440 is a gapful number since it is divisible by the number (30) 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 30661440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (52517040).

30661440 is an abundant number, since it is smaller than the sum of its proper divisors (74372640).

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

30661440 is a wasteful number, since it uses less digits than its factorization.

30661440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121 (or 70 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 24.

The square root of 30661440 is about 5537.2773092920. The cubic root of 30661440 is about 312.9902789361.

The spelling of 30661440 in words is "thirty million, six hundred sixty-one thousand, four hundred forty".