20696776156865 has 32 divisors (see below), whose sum is σ = 24997246354080. Its totient is φ = 16450374860800.

The previous prime is 20696776156853. The next prime is 20696776156867. The reversal of 20696776156865 is 56865167769602.

It is a happy number.

It can be written as a sum of positive squares in 16 ways, for example, as 54138120976 + 20642638035889 = 232676^2 + 4543417^2 .

It is not a de Polignac number, because 20696776156865 - 2⁶ = 20696776156801 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20696776156792 and 20696776156801.

It is not an unprimeable number, because it can be changed into a prime (20696776156867) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1801437041 + ... + 1801448529.

It is an arithmetic number, because the mean of its divisors is an integer number (781163948565).

Almost surely, 2^{20696776156865} is an apocalyptic number.

It is an amenable number.

20696776156865 is a deficient number, since it is larger than the sum of its proper divisors (4300470197215).

20696776156865 is a wasteful number, since it uses less digits than its factorization.

20696776156865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15253.

The product of its (nonzero) digits is 1371686400, while the sum is 74.

The spelling of 20696776156865 in words is "twenty trillion, six hundred ninety-six billion, seven hundred seventy-six million, one hundred fifty-six thousand, eight hundred sixty-five".