20897370 has 96 divisors (see below), whose sum is σ = 59793552. Its totient is φ = 5031936.

The previous prime is 20897353. The next prime is 20897377. The reversal of 20897370 is 7379802.

It can be written as a sum of positive squares in 8 ways, for example, as 5049009 + 15848361 = 2247^2 + 3981^2 .

It is not an unprimeable number, because it can be changed into a prime (20897377) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 61842 + ... + 62178.

Almost surely, 2^20897370 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20897370, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29896776).

20897370 is an abundant number, since it is smaller than the sum of its proper divisors (38896182).

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

20897370 is a wasteful number, since it uses less digits than its factorization.

20897370 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 416 (or 413 counting only the distinct ones).

The product of its (nonzero) digits is 21168, while the sum is 36.

The square root of 20897370 is about 4571.3641290101. The cubic root of 20897370 is about 275.4422415954.

The spelling of 20897370 in words is "twenty million, eight hundred ninety-seven thousand, three hundred seventy".