20281265637 has 4 divisors (see below), whose sum is σ = 27041687520. Its totient is φ = 13520843756.

The previous prime is 20281265633. The next prime is 20281265647. The reversal of 20281265637 is 73656218202.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20281265637 - 2² = 20281265633 is a prime.

It is a super-2 number, since 2×20281265637² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20281265633) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3380210937 + ... + 3380210942.

It is an arithmetic number, because the mean of its divisors is an integer number (6760421880).

Almost surely, 2^20281265637 is an apocalyptic number.

It is an amenable number.

20281265637 is a deficient number, since it is larger than the sum of its proper divisors (6760421883).

20281265637 is an equidigital number, since it uses as much as digits as its factorization.

20281265637 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6760421882.

The product of its (nonzero) digits is 241920, while the sum is 42.

The spelling of 20281265637 in words is "twenty billion, two hundred eighty-one million, two hundred sixty-five thousand, six hundred thirty-seven".