20657142 has 108 divisors (see below), whose sum is σ = 54740556. Its totient is φ = 5581440.

The previous prime is 20657141. The next prime is 20657149. The reversal of 20657142 is 24175602.

20657142 is a `hidden beast` number, since 2 + 0 + 657 + 1 + 4 + 2 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20657141) by changing a digit.

It is a polite number, since it can be written in 53 ways as a sum of consecutive naturals, for example, 1087209 + ... + 1087227.

It is an arithmetic number, because the mean of its divisors is an integer number (506857).

Almost surely, 2^20657142 is an apocalyptic number.

20657142 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 20657142, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27370278).

20657142 is an abundant number, since it is smaller than the sum of its proper divisors (34083414).

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

20657142 is a wasteful number, since it uses less digits than its factorization.

20657142 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91 (or 52 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 27.

The square root of 20657142 is about 4545.0128712689. The cubic root of 20657142 is about 274.3827123919.

The spelling of 20657142 in words is "twenty million, six hundred fifty-seven thousand, one hundred forty-two".