20331945 has 16 divisors (see below), whose sum is σ = 36145920. Its totient is φ = 10843632.

The previous prime is 20331917. The next prime is 20331953. The reversal of 20331945 is 54913302.

It is not a de Polignac number, because 20331945 - 2¹² = 20327849 is a prime.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

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

It is a Curzon 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, 75169 + ... + 75438.

It is an arithmetic number, because the mean of its divisors is an integer number (2259120).

Almost surely, 2^20331945 is an apocalyptic number.

It is an amenable number.

20331945 is a deficient number, since it is larger than the sum of its proper divisors (15813975).

20331945 is a wasteful number, since it uses less digits than its factorization.

20331945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 150621 (or 150615 counting only the distinct ones).

The product of its (nonzero) digits is 3240, while the sum is 27.

The square root of 20331945 is about 4509.0958073654. The cubic root of 20331945 is about 272.9352581654.

The spelling of 20331945 in words is "twenty million, three hundred thirty-one thousand, nine hundred forty-five".