20757408 has 192 divisors, whose sum is σ = 69672960. Its totient is φ = 5271552.

The previous prime is 20757403. The next prime is 20757421. The reversal of 20757408 is 80475702.

It is not an unprimeable number, because it can be changed into a prime (20757403) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 262713 + ... + 262791.

It is an arithmetic number, because the mean of its divisors is an integer number (362880).

Almost surely, 2^20757408 is an apocalyptic number.

20757408 is a gapful number since it is divisible by the number (28) 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 20757408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34836480).

20757408 is an abundant number, since it is smaller than the sum of its proper divisors (48915552).

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

20757408 is a wasteful number, since it uses less digits than its factorization.

20757408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 139 (or 131 counting only the distinct ones).

The product of its (nonzero) digits is 15680, while the sum is 33.

The square root of 20757408 is about 4556.0298506485. The cubic root of 20757408 is about 274.8259306122.

The spelling of 20757408 in words is "twenty million, seven hundred fifty-seven thousand, four hundred eight".