20459778 has 16 divisors (see below), whose sum is σ = 40966560. Its totient is φ = 6812096.

The previous prime is 20459773. The next prime is 20459797. The reversal of 20459778 is 87795402.

It is not an unprimeable number, because it can be changed into a prime (20459771) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6538 + ... + 9146.

It is an arithmetic number, because the mean of its divisors is an integer number (2560410).

Almost surely, 2^20459778 is an apocalyptic number.

20459778 is an abundant number, since it is smaller than the sum of its proper divisors (20506782).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20459778 is a wasteful number, since it uses less digits than its factorization.

20459778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3921.

The product of its (nonzero) digits is 141120, while the sum is 42.

The square root of 20459778 is about 4523.2486113412. The cubic root of 20459778 is about 273.5060719865.

The spelling of 20459778 in words is "twenty million, four hundred fifty-nine thousand, seven hundred seventy-eight".