20949457 has 16 divisors (see below), whose sum is σ = 23673600. Its totient is φ = 18420480.

The previous prime is 20949421. The next prime is 20949499. The reversal of 20949457 is 75494902.

It is a cyclic number.

It is not a de Polignac number, because 20949457 - 2⁷ = 20949329 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20949157) 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, 25107 + ... + 25927.

It is an arithmetic number, because the mean of its divisors is an integer number (1479600).

Almost surely, 2^20949457 is an apocalyptic number.

It is an amenable number.

20949457 is a deficient number, since it is larger than the sum of its proper divisors (2724143).

20949457 is a wasteful number, since it uses less digits than its factorization.

20949457 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 936.

The product of its (nonzero) digits is 90720, while the sum is 40.

The square root of 20949457 is about 4577.0576793394. The cubic root of 20949457 is about 275.6708996596.

The spelling of 20949457 in words is "twenty million, nine hundred forty-nine thousand, four hundred fifty-seven".