20501371489 has 9 divisors (see below), whose sum is σ = 20677983699. Its totient is φ = 20326258680.

The previous prime is 20501371427. The next prime is 20501371519. The reversal of 20501371489 is 98417310502.

The square root of 20501371489 is 143183.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 20202358225 + 299013264 = 142135^2 + 17292^2 .

It is not a de Polignac number, because 20501371489 - 2¹³ = 20501363297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20501377489) by changing a digit.

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 in 8 ways as a sum of consecutive naturals, for example, 18756427 + ... + 18757519.

Almost surely, 2^20501371489 is an apocalyptic number.

20501371489 is the 143183-rd square number.

20501371489 is the 71592-nd centered octagonal number.

It is an amenable number.

20501371489 is a deficient number, since it is larger than the sum of its proper divisors (176612210).

20501371489 is an frugal number, since it uses more digits than its factorization.

20501371489 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2448 (or 1224 counting only the distinct ones).

The product of its (nonzero) digits is 60480, while the sum is 40.

The spelling of 20501371489 in words is "twenty billion, five hundred one million, three hundred seventy-one thousand, four hundred eighty-nine".