20641021154 has 32 divisors (see below), whose sum is σ = 33750606960. Its totient is φ = 9410429952.

The previous prime is 20641021147. The next prime is 20641021213. The reversal of 20641021154 is 45112014602.

It can be written as a sum of positive squares in 8 ways, for example, as 8962976929 + 11678044225 = 94673^2 + 108065^2 .

It is a Harshad number since it is a multiple of its sum of digits (26).

It is a Curzon number.

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 15 ways as a sum of consecutive naturals, for example, 2756864 + ... + 2764340.

Almost surely, 2^20641021154 is an apocalyptic number.

20641021154 is a deficient number, since it is larger than the sum of its proper divisors (13109585806).

20641021154 is a wasteful number, since it uses less digits than its factorization.

20641021154 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8774.

The product of its (nonzero) digits is 1920, while the sum is 26.

Adding to 20641021154 its reverse (45112014602), we get a palindrome (65753035756).

The spelling of 20641021154 in words is "twenty billion, six hundred forty-one million, twenty-one thousand, one hundred fifty-four".