Search a number
-
+
87821491 is a prime number
BaseRepresentation
bin1010011110000…
…00110010110011
320010020210102211
411033000302303
5134440241431
612414152551
72114320222
oct517006263
9203223384
1087821491
114563364a
12254b2757
131526b4a4
14b940cb9
157a9b2b1
hex53c0cb3

87821491 has 2 divisors, whose sum is σ = 87821492. Its totient is φ = 87821490.

The previous prime is 87821479. The next prime is 87821509. The reversal of 87821491 is 19412878.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 87821491 - 29 = 87820979 is a prime.

It is a super-2 number, since 2×878214912 = 15425228562926162, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (87824491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43910745 + 43910746.

It is an arithmetic number, because the mean of its divisors is an integer number (43910746).

Almost surely, 287821491 is an apocalyptic number.

87821491 is a deficient number, since it is larger than the sum of its proper divisors (1).

87821491 is an equidigital number, since it uses as much as digits as its factorization.

87821491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32256, while the sum is 40.

The square root of 87821491 is about 9371.3121279787. The cubic root of 87821491 is about 444.4950565950.

The spelling of 87821491 in words is "eighty-seven million, eight hundred twenty-one thousand, four hundred ninety-one".