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81415 = 519857
BaseRepresentation
bin10011111000000111
311010200101
4103320013
510101130
61424531
7456235
oct237007
9133611
1081415
1156194
123b147
132b099
1421955
15191ca
hex13e07

81415 has 8 divisors (see below), whose sum is σ = 102960. Its totient is φ = 61632.

The previous prime is 81409. The next prime is 81421. The reversal of 81415 is 51418.

It is an interprime number because it is at equal distance from previous prime (81409) and next prime (81421).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81415 - 211 = 79367 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a junction number, because it is equal to n+sod(n) for n = 81392 and 81401.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 334 + ... + 523.

It is an arithmetic number, because the mean of its divisors is an integer number (12870).

281415 is an apocalyptic number.

81415 is a deficient number, since it is larger than the sum of its proper divisors (21545).

81415 is a wasteful number, since it uses less digits than its factorization.

81415 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 881.

The product of its digits is 160, while the sum is 19.

The square root of 81415 is about 285.3331386292. Note that the first 3 decimals coincide. The cubic root of 81415 is about 43.3412543048.

It can be divided in two parts, 81 and 415, that added together give a triangular number (496 = T31).

The spelling of 81415 in words is "eighty-one thousand, four hundred fifteen".

Divisors: 1 5 19 95 857 4285 16283 81415