623533440 has 64 divisors (see below), whose sum is σ = 1987518960. Its totient is φ = 166275072.

The previous prime is 623533439. The next prime is 623533441. The reversal of 623533440 is 44335326.

It is an interprime number because it is at equal distance from previous prime (623533439) and next prime (623533441).

It is a tau number, because it is divible by the number of its divisors (64).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 623533398 and 623533407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (623533441) 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, 160459 + ... + 164298.

Almost surely, 2^623533440 is an apocalyptic number.

623533440 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

623533440 is an abundant number, since it is smaller than the sum of its proper divisors (1363985520).

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

623533440 is a wasteful number, since it uses less digits than its factorization.

623533440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 324779 (or 324767 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 30.

The square root of 623533440 is about 24970.6515733971. The cubic root of 623533440 is about 854.3187076355.

Adding to 623533440 its reverse (44335326), we get a palindrome (667868766).

The spelling of 623533440 in words is "six hundred twenty-three million, five hundred thirty-three thousand, four hundred forty".