20637428 has 36 divisors (see below), whose sum is σ = 42632352. Its totient is φ = 8714160.

The previous prime is 20637403. The next prime is 20637437. The reversal of 20637428 is 82473602.

It is a junction number, because it is equal to n+sod(n) for n = 20637394 and 20637403.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13175 + ... + 14657.

It is an arithmetic number, because the mean of its divisors is an integer number (1184232).

Almost surely, 2^20637428 is an apocalyptic number.

20637428 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 20637428, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21316176).

20637428 is an abundant number, since it is smaller than the sum of its proper divisors (21994924).

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

20637428 is a wasteful number, since it uses less digits than its factorization.

20637428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1572 (or 1563 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 32.

The square root of 20637428 is about 4542.8436028549. The cubic root of 20637428 is about 274.2953995319.

The spelling of 20637428 in words is "twenty million, six hundred thirty-seven thousand, four hundred twenty-eight".