20537890 has 8 divisors (see below), whose sum is σ = 36968220. Its totient is φ = 8215152.

The previous prime is 20537861. The next prime is 20537899. The reversal of 20537890 is 9873502.

It can be written as a sum of positive squares in 2 ways, for example, as 19722481 + 815409 = 4441^2 + 903^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (20537899) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1026885 + ... + 1026904.

Almost surely, 2^20537890 is an apocalyptic number.

20537890 is a deficient number, since it is larger than the sum of its proper divisors (16430330).

20537890 is a wasteful number, since it uses less digits than its factorization.

20537890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2053796.

The product of its (nonzero) digits is 15120, while the sum is 34.

The square root of 20537890 is about 4531.8748879465. The cubic root of 20537890 is about 273.8536967363.

The spelling of 20537890 in words is "twenty million, five hundred thirty-seven thousand, eight hundred ninety".