20501972 has 6 divisors (see below), whose sum is σ = 35878458. Its totient is φ = 10250984.

The previous prime is 20501911. The next prime is 20501981. The reversal of 20501972 is 27910502.

It can be written as a sum of positive squares in only one way, i.e., 15100996 + 5400976 = 3886^2 + 2324^2 .

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 2562743 + ... + 2562750.

It is an arithmetic number, because the mean of its divisors is an integer number (5979743).

Almost surely, 2^20501972 is an apocalyptic number.

It is an amenable number.

20501972 is a deficient number, since it is larger than the sum of its proper divisors (15376486).

20501972 is a wasteful number, since it uses less digits than its factorization.

20501972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5125497 (or 5125495 counting only the distinct ones).

The product of its (nonzero) digits is 1260, while the sum is 26.

The square root of 20501972 is about 4527.9103348013. The cubic root of 20501972 is about 273.6939591851.

The spelling of 20501972 in words is "twenty million, five hundred one thousand, nine hundred seventy-two".