20351790 has 32 divisors (see below), whose sum is σ = 54272160. Its totient is φ = 5427072.

The previous prime is 20351783. The next prime is 20351791. The reversal of 20351790 is 9715302.

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

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20351791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 37419 + ... + 37958.

It is an arithmetic number, because the mean of its divisors is an integer number (1696005).

Almost surely, 2^20351790 is an apocalyptic number.

20351790 is an abundant number, since it is smaller than the sum of its proper divisors (33920370).

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

20351790 is a wasteful number, since it uses less digits than its factorization.

20351790 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75393 (or 75387 counting only the distinct ones).

The product of its (nonzero) digits is 1890, while the sum is 27.

The square root of 20351790 is about 4511.2958227099. The cubic root of 20351790 is about 273.0240287991.

The spelling of 20351790 in words is "twenty million, three hundred fifty-one thousand, seven hundred ninety".