20631760 has 40 divisors (see below), whose sum is σ = 49628520. Its totient is φ = 7967232.

The previous prime is 20631757. The next prime is 20631763. The reversal of 20631760 is 6713602.

It is an interprime number because it is at equal distance from previous prime (20631757) and next prime (20631763).

It can be written as a sum of positive squares in 4 ways, for example, as 345744 + 20286016 = 588^2 + 4504^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20631763) 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 7 ways as a sum of consecutive naturals, for example, 2127 + ... + 6766.

It is an arithmetic number, because the mean of its divisors is an integer number (1240713).

Almost surely, 2^20631760 is an apocalyptic number.

20631760 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20631760 is an abundant number, since it is smaller than the sum of its proper divisors (28996760).

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

20631760 is a wasteful number, since it uses less digits than its factorization.

20631760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8935 (or 8929 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 25.

The square root of 20631760 is about 4542.2197216779. The cubic root of 20631760 is about 274.2702857972.

The spelling of 20631760 in words is "twenty million, six hundred thirty-one thousand, seven hundred sixty".