20849661 has 24 divisors (see below), whose sum is σ = 35917440. Its totient is φ = 11395296.

The previous prime is 20849659. The next prime is 20849677. The reversal of 20849661 is 16694802.

It is not a de Polignac number, because 20849661 - 2¹ = 20849659 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20849641) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5746 + ... + 8643.

It is an arithmetic number, because the mean of its divisors is an integer number (1496560).

Almost surely, 2^20849661 is an apocalyptic number.

20849661 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

20849661 is a deficient number, since it is larger than the sum of its proper divisors (15067779).

20849661 is a wasteful number, since it uses less digits than its factorization.

20849661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14425 (or 14422 counting only the distinct ones).

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

The square root of 20849661 is about 4566.1429018374. The cubic root of 20849661 is about 275.2324689936.

The spelling of 20849661 in words is "twenty million, eight hundred forty-nine thousand, six hundred sixty-one".