20394124865 has 8 divisors (see below), whose sum is σ = 25316844840. Its totient is φ = 15752703232.

The previous prime is 20394124859. The next prime is 20394124931. The reversal of 20394124865 is 56842149302.

It is a Cunningham number, because it is equal to 142808²+1.

It can be written as a sum of positive squares in 4 ways, for example, as 1 + 20394124864 = 1^2 + 142808^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20394124865 - 2¹⁴ = 20394108481 is a prime.

It is a super-2 number, since 2×20394124865² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 70324424 + ... + 70324713.

It is an arithmetic number, because the mean of its divisors is an integer number (3164605605).

Almost surely, 2^20394124865 is an apocalyptic number.

It is an amenable number.

20394124865 is a deficient number, since it is larger than the sum of its proper divisors (4922719975).

20394124865 is a wasteful number, since it uses less digits than its factorization.

20394124865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 140649171.

The product of its (nonzero) digits is 414720, while the sum is 44.

The spelling of 20394124865 in words is "twenty billion, three hundred ninety-four million, one hundred twenty-four thousand, eight hundred sixty-five".