21973547635157 has 2 divisors, whose sum is σ = 21973547635158. Its totient is φ = 21973547635156.

The previous prime is 21973547635111. The next prime is 21973547635213. The reversal of 21973547635157 is 75153674537912.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15512144594116 + 6461403041041 = 3938546^2 + 2541929^2 .

It is a cyclic number.

It is not a de Polignac number, because 21973547635157 - 2⁸ = 21973547634901 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21973547635093 and 21973547635102.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21973547635757) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10986773817578 + 10986773817579.

It is an arithmetic number, because the mean of its divisors is an integer number (10986773817579).

Almost surely, 2^{21973547635157} is an apocalyptic number.

It is an amenable number.

21973547635157 is a deficient number, since it is larger than the sum of its proper divisors (1).

21973547635157 is an equidigital number, since it uses as much as digits as its factorization.

21973547635157 is an evil number, because the sum of its binary digits is even.

The product of its digits is 166698000, while the sum is 65.

The spelling of 21973547635157 in words is "twenty-one trillion, nine hundred seventy-three billion, five hundred forty-seven million, six hundred thirty-five thousand, one hundred fifty-seven".