20558945 has 16 divisors (see below), whose sum is σ = 27542592. Its totient is φ = 14602560.

The previous prime is 20558929. The next prime is 20558953. The reversal of 20558945 is 54985502.

It is not a de Polignac number, because 20558945 - 2⁴ = 20558929 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20558899 and 20558908.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1982 + ... + 6711.

It is an arithmetic number, because the mean of its divisors is an integer number (1721412).

Almost surely, 2^20558945 is an apocalyptic number.

It is an amenable number.

20558945 is a deficient number, since it is larger than the sum of its proper divisors (6983647).

20558945 is a wasteful number, since it uses less digits than its factorization.

20558945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8752.

The product of its (nonzero) digits is 72000, while the sum is 38.

The square root of 20558945 is about 4534.1972828716. The cubic root of 20558945 is about 273.9472477342.

The spelling of 20558945 in words is "twenty million, five hundred fifty-eight thousand, nine hundred forty-five".