20734240465 has 4 divisors (see below), whose sum is σ = 24881088564. Its totient is φ = 16587392368.

The previous prime is 20734240393. The next prime is 20734240481. The reversal of 20734240465 is 56404243702.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 56404243702 = 2 ⋅28202121851.

It can be written as a sum of positive squares in 2 ways, for example, as 13877075601 + 6857164864 = 117801^2 + 82808^2 .

It is a cyclic number.

It is not a de Polignac number, because 20734240465 - 2²³ = 20725851857 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2073424042 + ... + 2073424051.

It is an arithmetic number, because the mean of its divisors is an integer number (6220272141).

Almost surely, 2^20734240465 is an apocalyptic number.

It is an amenable number.

20734240465 is a deficient number, since it is larger than the sum of its proper divisors (4146848099).

20734240465 is an equidigital number, since it uses as much as digits as its factorization.

20734240465 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4146848098.

The product of its (nonzero) digits is 161280, while the sum is 37.

The spelling of 20734240465 in words is "twenty billion, seven hundred thirty-four million, two hundred forty thousand, four hundred sixty-five".