20265515449 has 3 divisors (see below), whose sum is σ = 20265657807. Its totient is φ = 20265373092.

The previous prime is 20265515447. The next prime is 20265515453. The reversal of 20265515449 is 94451556202.

The square root of 20265515449 is 142357.

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

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 177555625 + 20087959824 = 13325^2 + 141732^2 .

It is not a de Polignac number, because 20265515449 - 2¹ = 20265515447 is a prime.

It is a super-2 number, since 2×20265515449² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20265515447) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 71179 + ... + 213535.

It is an arithmetic number, because the mean of its divisors is an integer number (6755219269).

Almost surely, 2^20265515449 is an apocalyptic number.

20265515449 is the 142357-th square number.

20265515449 is the 71179-th centered octagonal number.

It is an amenable number.

20265515449 is a deficient number, since it is larger than the sum of its proper divisors (142358).

20265515449 is an frugal number, since it uses more digits than its factorization.

20265515449 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 284714 (or 142357 counting only the distinct ones).

The product of its (nonzero) digits is 432000, while the sum is 43.

The spelling of 20265515449 in words is "twenty billion, two hundred sixty-five million, five hundred fifteen thousand, four hundred forty-nine".