636620240 has 40 divisors (see below), whose sum is σ = 1483595520. Its totient is φ = 254054016.

The previous prime is 636620239. The next prime is 636620249. The reversal of 636620240 is 42026636.

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 (636620249) 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, 26057 + ... + 44183.

It is an arithmetic number, because the mean of its divisors is an integer number (37089888).

Almost surely, 2^636620240 is an apocalyptic number.

It is an amenable number.

636620240 is an abundant number, since it is smaller than the sum of its proper divisors (846975280).

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

636620240 is a wasteful number, since it uses less digits than its factorization.

636620240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18579 (or 18573 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 29.

The square root of 636620240 is about 25231.3344871015. The cubic root of 636620240 is about 860.2542244628.

Adding to 636620240 its reverse (42026636), we get a palindrome (678646876).

The spelling of 636620240 in words is "six hundred thirty-six million, six hundred twenty thousand, two hundred forty".