40023990 has 64 divisors (see below), whose sum is σ = 107320320. Its totient is φ = 10614240.

The previous prime is 40023989. The next prime is 40024009. The reversal of 40023990 is 9932004.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 72897 + ... + 73443.

It is an arithmetic number, because the mean of its divisors is an integer number (1676880).

Almost surely, 2^40023990 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 40023990, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (53660160).

40023990 is an abundant number, since it is smaller than the sum of its proper divisors (67296330).

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

40023990 is a wasteful number, since it uses less digits than its factorization.

40023990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 834 (or 828 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 27.

The square root of 40023990 is about 6326.4516120808. The cubic root of 40023990 is about 342.0635462097.

Adding to 40023990 its reverse (9932004), we get a palindrome (49955994).

The spelling of 40023990 in words is "forty million, twenty-three thousand, nine hundred ninety".