20406750 has 192 divisors, whose sum is σ = 65774592. Its totient is φ = 4118400.

The previous prime is 20406697. The next prime is 20406767. The reversal of 20406750 is 5760402.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 20406750.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 887239 + ... + 887261.

It is an arithmetic number, because the mean of its divisors is an integer number (342576).

Almost surely, 2^20406750 is an apocalyptic number.

20406750 is the 2415-th nonagonal number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20406750, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32887296).

20406750 is an abundant number, since it is smaller than the sum of its proper divisors (45367842).

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

20406750 is a wasteful number, since it uses less digits than its factorization.

20406750 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76 (or 53 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 24.

The square root of 20406750 is about 4517.3830920125. The cubic root of 20406750 is about 273.2695749893.

The spelling of 20406750 in words is "twenty million, four hundred six thousand, seven hundred fifty".