20750040 has 64 divisors (see below), whose sum is σ = 69170400. Its totient is φ = 5533056.

The previous prime is 20750027. The next prime is 20750069. The reversal of 20750040 is 4005702.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 20749995 and 20750022.

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, 8527 + ... + 10686.

Almost surely, 2^20750040 is an apocalyptic number.

20750040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20750040 is an abundant number, since it is smaller than the sum of its proper divisors (48420360).

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

20750040 is a wasteful number, since it uses less digits than its factorization.

20750040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19233 (or 19223 counting only the distinct ones).

The product of its (nonzero) digits is 280, while the sum is 18.

The square root of 20750040 is about 4555.2211801404. The cubic root of 20750040 is about 274.7934095786.

Adding to 20750040 its reverse (4005702), we get a palindrome (24755742).

The spelling of 20750040 in words is "twenty million, seven hundred fifty thousand, forty".