20986461 has 6 divisors (see below), whose sum is σ = 30313790. Its totient is φ = 13990968.

The previous prime is 20986447. The next prime is 20986481. The reversal of 20986461 is 16468902.

20986461 is a `hidden beast` number, since 2 + 0 + 9 + 8 + 646 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 20985561 + 900 = 4581^2 + 30^2 .

It is not a de Polignac number, because 20986461 - 2⁶ = 20986397 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20986481) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1165906 + ... + 1165923.

Almost surely, 2^20986461 is an apocalyptic number.

It is an amenable number.

20986461 is a deficient number, since it is larger than the sum of its proper divisors (9327329).

20986461 is a wasteful number, since it uses less digits than its factorization.

20986461 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2331835 (or 2331832 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 20986461 is about 4581.0982307739. The cubic root of 20986461 is about 275.8331142974.

The spelling of 20986461 in words is "twenty million, nine hundred eighty-six thousand, four hundred sixty-one".