20948409 has 16 divisors (see below), whose sum is σ = 31622400. Its totient is φ = 13701168.

The previous prime is 20948399. The next prime is 20948419. The reversal of 20948409 is 90484902.

It is a happy number.

20948409 is a `hidden beast` number, since 209 + 48 + 409 = 666.

It is an interprime number because it is at equal distance from previous prime (20948399) and next prime (20948419).

It is not a de Polignac number, because 20948409 - 2¹¹ = 20946361 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20948419) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5889 + ... + 8750.

It is an arithmetic number, because the mean of its divisors is an integer number (1976400).

Almost surely, 2^20948409 is an apocalyptic number.

It is an amenable number.

20948409 is a deficient number, since it is larger than the sum of its proper divisors (10673991).

20948409 is a wasteful number, since it uses less digits than its factorization.

20948409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14701 (or 14695 counting only the distinct ones).

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

The square root of 20948409 is about 4576.9431938795. The cubic root of 20948409 is about 275.6663027558. Note that the first 3 decimals are identical.

The spelling of 20948409 in words is "twenty million, nine hundred forty-eight thousand, four hundred nine".