623435640 has 64 divisors (see below), whose sum is σ = 1872063360. Its totient is φ = 166093440.

The previous prime is 623435633. The next prime is 623435647. The reversal of 623435640 is 46534326.

It is an interprime number because it is at equal distance from previous prime (623435633) and next prime (623435647).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (623435647) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 186867 + ... + 190173.

It is an arithmetic number, because the mean of its divisors is an integer number (29250990).

Almost surely, 2^623435640 is an apocalyptic number.

623435640 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

623435640 is an abundant number, since it is smaller than the sum of its proper divisors (1248627720).

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

623435640 is a wasteful number, since it uses less digits than its factorization.

623435640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4892 (or 4888 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 33.

The square root of 623435640 is about 24968.6931976826. The cubic root of 623435640 is about 854.2740392275.

Adding to 623435640 its reverse (46534326), we get a palindrome (669969966).

The spelling of 623435640 in words is "six hundred twenty-three million, four hundred thirty-five thousand, six hundred forty".