20920170 has 64 divisors (see below), whose sum is σ = 52793856. Its totient is φ = 5299200.

The previous prime is 20920157. The next prime is 20920181. The reversal of 20920170 is 7102902.

It is a happy number.

It is a super-3 number, since 3×20920170³ (a number of 23 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 51970 + ... + 52370.

It is an arithmetic number, because the mean of its divisors is an integer number (824904).

Almost surely, 2^20920170 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20920170, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26396928).

20920170 is an abundant number, since it is smaller than the sum of its proper divisors (31873686).

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

20920170 is a wasteful number, since it uses less digits than its factorization.

20920170 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 495.

The product of its (nonzero) digits is 252, while the sum is 21.

The square root of 20920170 is about 4573.8572343264. The cubic root of 20920170 is about 275.5423786069.

The spelling of 20920170 in words is "twenty million, nine hundred twenty thousand, one hundred seventy".