20661016 has 8 divisors (see below), whose sum is σ = 38739420. Its totient is φ = 10330504.

The previous prime is 20661013. The next prime is 20661019. The reversal of 20661016 is 61016602.

It is an interprime number because it is at equal distance from previous prime (20661013) and next prime (20661019).

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20661013) 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 as a sum of consecutive naturals, namely, 1291306 + ... + 1291321.

Almost surely, 2^20661016 is an apocalyptic number.

It is an amenable number.

20661016 is a deficient number, since it is larger than the sum of its proper divisors (18078404).

20661016 is a wasteful number, since it uses less digits than its factorization.

20661016 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2582633 (or 2582629 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 22.

The square root of 20661016 is about 4545.4390327008. The cubic root of 20661016 is about 274.3998637188.

Adding to 20661016 its reverse (61016602), we get a palindrome (81677618).

The spelling of 20661016 in words is "twenty million, six hundred sixty-one thousand, sixteen".