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21100000157 is a prime number
BaseRepresentation
bin10011101001101010…
…000111001110011101
32000110111101001210022
4103221222013032131
5321203100001112
613405422121525
71344610020305
oct235152071635
960414331708
1021100000157
118a48444465
12410a4202a5
131cb35586c2
141042424605
15837601d72
hex4e9a8739d

21100000157 has 2 divisors, whose sum is σ = 21100000158. Its totient is φ = 21100000156.

The previous prime is 21100000151. The next prime is 21100000219. The reversal of 21100000157 is 75100000112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16959592441 + 4140407716 = 130229^2 + 64346^2 .

It is a cyclic number.

It is not a de Polignac number, because 21100000157 - 212 = 21099996061 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21100000151) by changing a digit.

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 as a sum of consecutive naturals, namely, 10550000078 + 10550000079.

It is an arithmetic number, because the mean of its divisors is an integer number (10550000079).

Almost surely, 221100000157 is an apocalyptic number.

It is an amenable number.

21100000157 is a deficient number, since it is larger than the sum of its proper divisors (1).

21100000157 is an equidigital number, since it uses as much as digits as its factorization.

21100000157 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 70, while the sum is 17.

Adding to 21100000157 its reverse (75100000112), we get a palindrome (96200000269).

The spelling of 21100000157 in words is "twenty-one billion, one hundred million, one hundred fifty-seven", and thus it is an aban number.