20495490 has 64 divisors (see below), whose sum is σ = 53101440. Its totient is φ = 5045760.

The previous prime is 20495473. The next prime is 20495491. The reversal of 20495490 is 9459402.

It is a super-2 number, since 2×20495490² = 840130220680200, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20495491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 22932 + ... + 23808.

It is an arithmetic number, because the mean of its divisors is an integer number (829710).

Almost surely, 2^20495490 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20495490, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26550720).

20495490 is an abundant number, since it is smaller than the sum of its proper divisors (32605950).

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

20495490 is a wasteful number, since it uses less digits than its factorization.

20495490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 947.

The product of its (nonzero) digits is 12960, while the sum is 33.

The square root of 20495490 is about 4527.1944954906. The cubic root of 20495490 is about 273.6651120211.

It can be divided in two parts, 20 and 495490, that added together give a triangular number (495510 = T₉₉₅).

The spelling of 20495490 in words is "twenty million, four hundred ninety-five thousand, four hundred ninety".