23351640 has 64 divisors (see below), whose sum is σ = 75448800. Its totient is φ = 5747712.

The previous prime is 23351639. The next prime is 23351651. The reversal of 23351640 is 4615332.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 23351640.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5925 + ... + 9044.

Almost surely, 2^23351640 is an apocalyptic number.

23351640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

23351640 is an abundant number, since it is smaller than the sum of its proper divisors (52097160).

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

23351640 is a wasteful number, since it uses less digits than its factorization.

23351640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14996 (or 14992 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 24.

The square root of 23351640 is about 4832.3534638931. The cubic root of 23351640 is about 285.8286746732.

Adding to 23351640 its reverse (4615332), we get a palindrome (27966972).

The spelling of 23351640 in words is "twenty-three million, three hundred fifty-one thousand, six hundred forty".