20212665 has 16 divisors (see below), whose sum is σ = 35280576. Its totient is φ = 9800000.

The previous prime is 20212639. The next prime is 20212667. The reversal of 20212665 is 56621202.

It is a de Polignac number, because none of the positive numbers 2^k-20212665 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20212667) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 61086 + ... + 61415.

It is an arithmetic number, because the mean of its divisors is an integer number (2205036).

Almost surely, 2^20212665 is an apocalyptic number.

It is an amenable number.

20212665 is a deficient number, since it is larger than the sum of its proper divisors (15067911).

20212665 is a wasteful number, since it uses less digits than its factorization.

20212665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122520.

The product of its (nonzero) digits is 1440, while the sum is 24.

The square root of 20212665 is about 4495.8497528276. The cubic root of 20212665 is about 272.4004742736.

Adding to 20212665 its reverse (56621202), we get a palindrome (76833867).

The spelling of 20212665 in words is "twenty million, two hundred twelve thousand, six hundred sixty-five".