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381077581 = 18114512
BaseRepresentation
bin10110101101101…
…100100001001101
3222120001202011111
4112231230201031
51240023440311
6101451452021
712305051233
oct2655544115
9876052144
10381077581
11186121255
12a7757011
1360c477c1
143887a953
15236c6d21
hex16b6c84d

381077581 has 6 divisors (see below), whose sum is σ = 383447246. Its totient is φ = 378711000.

The previous prime is 381077569. The next prime is 381077621. The reversal of 381077581 is 185770183.

It is a happy number.

It is the 7970-th star number.

It can be written as a sum of positive squares in only one way, i.e., 210540100 + 170537481 = 14510^2 + 13059^2 .

It is not a de Polignac number, because 381077581 - 25 = 381077549 is a prime.

It is a super-2 number, since 2×3810775812 = 290440245481623122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (381077531) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 261906 + ... + 263356.

Almost surely, 2381077581 is an apocalyptic number.

It is an amenable number.

381077581 is a deficient number, since it is larger than the sum of its proper divisors (2369665).

381077581 is an frugal number, since it uses more digits than its factorization.

381077581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3083 (or 1632 counting only the distinct ones).

The product of its (nonzero) digits is 47040, while the sum is 40.

The square root of 381077581 is about 19521.2084923040. The cubic root of 381077581 is about 724.9996550137. Note that the first 3 decimals are identical.

The spelling of 381077581 in words is "three hundred eighty-one million, seventy-seven thousand, five hundred eighty-one".

Divisors: 1 181 1451 262631 2105401 381077581