20618956145 has 8 divisors (see below), whose sum is σ = 25411470504. Its totient is φ = 16049349504.

The previous prime is 20618956133. The next prime is 20618956151. The reversal of 20618956145 is 54165981602.

It can be written as a sum of positive squares in 4 ways, for example, as 7257676864 + 13361279281 = 85192^2 + 115591^2 .

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 20618956145 - 2¹⁶ = 20618890609 is a prime.

It is a super-2 number, since 2×20618956145² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 20618956145.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 55726724 + ... + 55727093.

It is an arithmetic number, because the mean of its divisors is an integer number (3176433813).

Almost surely, 2^20618956145 is an apocalyptic number.

It is an amenable number.

20618956145 is a deficient number, since it is larger than the sum of its proper divisors (4792514359).

20618956145 is a wasteful number, since it uses less digits than its factorization.

20618956145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111453859.

The product of its (nonzero) digits is 518400, while the sum is 47.

The spelling of 20618956145 in words is "twenty billion, six hundred eighteen million, nine hundred fifty-six thousand, one hundred forty-five".