20661084 has 36 divisors (see below), whose sum is σ = 54499536. Its totient is φ = 6587328.

The previous prime is 20661049. The next prime is 20661101. The reversal of 20661084 is 48016602.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-3 number, since 3×20661084³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11649 + ... + 13304.

It is an arithmetic number, because the mean of its divisors is an integer number (1513876).

Almost surely, 2^20661084 is an apocalyptic number.

It is an amenable number.

20661084 is an abundant number, since it is smaller than the sum of its proper divisors (33838452).

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

20661084 is a wasteful number, since it uses less digits than its factorization.

20661084 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24986 (or 24981 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 20661084 is about 4545.4465127202. The cubic root of 20661084 is about 274.4001647555.

Adding to 20661084 its reverse (48016602), we get a palindrome (68677686).

The spelling of 20661084 in words is "twenty million, six hundred sixty-one thousand, eighty-four".