20661316 has 24 divisors (see below), whose sum is σ = 39118464. Its totient is φ = 9492000.

The previous prime is 20661301. The next prime is 20661323. The reversal of 20661316 is 61316602.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12261 + ... + 13843.

It is an arithmetic number, because the mean of its divisors is an integer number (1629936).

Almost surely, 2^20661316 is an apocalyptic number.

20661316 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

20661316 is a deficient number, since it is larger than the sum of its proper divisors (18457148).

20661316 is a wasteful number, since it uses less digits than its factorization.

20661316 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1851 (or 1849 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 25.

The square root of 20661316 is about 4545.4720326936. The cubic root of 20661316 is about 274.4011918168.

Adding to 20661316 its reverse (61316602), we get a palindrome (81977918).

The spelling of 20661316 in words is "twenty million, six hundred sixty-one thousand, three hundred sixteen".