20894687945 has 8 divisors (see below), whose sum is σ = 25241905800. Its totient is φ = 16603563520.

The previous prime is 20894687911. The next prime is 20894687951. The reversal of 20894687945 is 54978649802.

It can be written as a sum of positive squares in 4 ways, for example, as 369254656 + 20525433289 = 19216^2 + 143267^2 .

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

It is not a de Polignac number, because 20894687945 - 2²² = 20890493641 is a prime.

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, 14022536 + ... + 14024025.

It is an arithmetic number, because the mean of its divisors is an integer number (3155238225).

Almost surely, 2^20894687945 is an apocalyptic number.

It is an amenable number.

20894687945 is a deficient number, since it is larger than the sum of its proper divisors (4347217855).

20894687945 is a wasteful number, since it uses less digits than its factorization.

20894687945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28046715.

The product of its (nonzero) digits is 34836480, while the sum is 62.

The spelling of 20894687945 in words is "twenty billion, eight hundred ninety-four million, six hundred eighty-seven thousand, nine hundred forty-five".