20445902 has 4 divisors (see below), whose sum is σ = 30668856. Its totient is φ = 10222950.

The previous prime is 20445889. The next prime is 20445923. The reversal of 20445902 is 20954402.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5111474 + ... + 5111477.

It is an arithmetic number, because the mean of its divisors is an integer number (7667214).

Almost surely, 2^20445902 is an apocalyptic number.

20445902 is a deficient number, since it is larger than the sum of its proper divisors (10222954).

20445902 is a wasteful number, since it uses less digits than its factorization.

20445902 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10222953.

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 20445902 is about 4521.7144978426. The cubic root of 20445902 is about 273.4442266013. Note that the first 3 decimals are identical.

The spelling of 20445902 in words is "twenty million, four hundred forty-five thousand, nine hundred two".