Search a number
BaseRepresentation
bin1110011111101111010101
321011001122112
432133233111
51433100041
6213240405
744204531
oct16375725
97131575
103800021
112166015
121333105
13a30844
1470cbc1
15500deb
hex39fbd5

3800021 has 2 divisors, whose sum is σ = 3800022. Its totient is φ = 3800020.

The previous prime is 3799973. The next prime is 3800051. The reversal of 3800021 is 1200083.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2146225 + 1653796 = 1465^2 + 1286^2 .

It is an emirp because it is prime and its reverse (1200083) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2k-3800021 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 3799969 and 3800005.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3800051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1900010 + 1900011.

It is an arithmetic number, because the mean of its divisors is an integer number (1900011).

Almost surely, 23800021 is an apocalyptic number.

It is an amenable number.

3800021 is a deficient number, since it is larger than the sum of its proper divisors (1).

3800021 is an equidigital number, since it uses as much as digits as its factorization.

3800021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 3800021 is about 1949.3642553407. The cubic root of 3800021 is about 156.0493625291.

Subtracting from 3800021 its product of nonzero digits (48), we obtain a palindrome (3799973).

The spelling of 3800021 in words is "three million, eight hundred thousand, twenty-one".