20311604 has 6 divisors (see below), whose sum is σ = 35545314. Its totient is φ = 10155800.

The previous prime is 20311601. The next prime is 20311607. The reversal of 20311604 is 40611302.

It is an interprime number because it is at equal distance from previous prime (20311601) and next prime (20311607).

It can be written as a sum of positive squares in only one way, i.e., 14455204 + 5856400 = 3802^2 + 2420^2 .

It is a super-2 number, since 2×20311604² = 825122514105632, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20311601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2538947 + ... + 2538954.

It is an arithmetic number, because the mean of its divisors is an integer number (5924219).

Almost surely, 2^20311604 is an apocalyptic number.

It is an amenable number.

20311604 is a deficient number, since it is larger than the sum of its proper divisors (15233710).

20311604 is a wasteful number, since it uses less digits than its factorization.

20311604 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5077905 (or 5077903 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 20311604 is about 4506.8396909586. The cubic root of 20311604 is about 272.8442088580.

Adding to 20311604 its reverse (40611302), we get a palindrome (60922906).

The spelling of 20311604 in words is "twenty million, three hundred eleven thousand, six hundred four".