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28740031 is a prime number
BaseRepresentation
bin110110110100…
…0100110111111
32000002010220121
41231220212333
524324140111
62503555411
7466200115
oct155504677
960063817
1028740031
111524a8a1
12975bb67
135c53648
143b61ab5
1527ca871
hex1b689bf

28740031 has 2 divisors, whose sum is σ = 28740032. Its totient is φ = 28740030.

The previous prime is 28740029. The next prime is 28740037. The reversal of 28740031 is 13004782.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 28740031 - 21 = 28740029 is a prime.

It is a super-2 number, since 2×287400312 = 1651978763761922, which contains 22 as substring.

Together with 28740029, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 28739978 and 28740005.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28740037) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14370015 + 14370016.

It is an arithmetic number, because the mean of its divisors is an integer number (14370016).

Almost surely, 228740031 is an apocalyptic number.

28740031 is the 2398-th centered decagonal number.

28740031 is a deficient number, since it is larger than the sum of its proper divisors (1).

28740031 is an equidigital number, since it uses as much as digits as its factorization.

28740031 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1344, while the sum is 25.

The square root of 28740031 is about 5360.9729527391. The cubic root of 28740031 is about 306.3108713654.

The spelling of 28740031 in words is "twenty-eight million, seven hundred forty thousand, thirty-one".