1951 has 2 divisors, whose sum is σ = 1952.
Its totient is φ = 1950.
The previous prime is 1949. The next prime is 1973. The reversal of 1951 is 1591.
It is a weak prime.
It is a cyclic number.
It is not a de Polignac number, because 1951 - 21 = 1949 is a prime.
Together with 1949, it forms a pair of twin primes.
It is a plaindrome in base 12 and base 16.
It is a nialpdrome in base 13.
It is a zygodrome in base 2.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (1901) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 975 + 976.
It is an arithmetic number, because the mean of its divisors is an integer number (976).
1951 is the 26-th hex number.
1951 is a deficient number, since it is larger than the sum of its proper divisors (1).
1951 is an equidigital number, since it uses as much as digits as its factorization.
1951 is an odious number, because the sum of its binary digits is odd.
The product of its digits is 45, while the sum is 16.
The square root of 1951 is about 44.1701256507.
The cubic root of 1951 is about 12.4954650216.
It can be divided in two parts, 195 and 1, that added together give a square (196 = 142).
The spelling of 1951 in words is "one thousand, nine hundred fifty-one".