20438856145 has 8 divisors (see below), whose sum is σ = 24566382504. Its totient is φ = 16324581504.

The previous prime is 20438856143. The next prime is 20438856223. The reversal of 20438856145 is 54165883402.

It can be written as a sum of positive squares in 4 ways, for example, as 2085109569 + 18353746576 = 45663^2 + 135476^2 .

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 20438856145 - 2¹ = 20438856143 is a prime.

It is a super-2 number, since 2×20438856145² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20438856095 and 20438856104.

It is not an unprimeable number, because it can be changed into a prime (20438856143) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3309534 + ... + 3315703.

It is an arithmetic number, because the mean of its divisors is an integer number (3070797813).

Almost surely, 2^20438856145 is an apocalyptic number.

It is an amenable number.

20438856145 is a deficient number, since it is larger than the sum of its proper divisors (4127526359).

20438856145 is an equidigital number, since it uses as much as digits as its factorization.

20438856145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6625859.

The product of its (nonzero) digits is 921600, while the sum is 46.

The spelling of 20438856145 in words is "twenty billion, four hundred thirty-eight million, eight hundred fifty-six thousand, one hundred forty-five".