951981 has 4 divisors (see below), whose sum is σ = 1269312. Its totient is φ = 634652.

The previous prime is 951967. The next prime is 951997. The reversal of 951981 is 189159.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 951981 - 2⁹ = 951469 is a prime.

It is a super-2 number, since 2×951981² = 1812535648722, which contains 22 as substring.

It is an Ulam number.

It is a D-number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 951981.

It is not an unprimeable number, because it can be changed into a prime (951911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 158661 + ... + 158666.

It is an arithmetic number, because the mean of its divisors is an integer number (317328).

2⁹⁵¹⁹⁸¹ is an apocalyptic number.

It is an amenable number.

951981 is a deficient number, since it is larger than the sum of its proper divisors (317331).

951981 is a wasteful number, since it uses less digits than its factorization.

951981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 317330.

The product of its digits is 3240, while the sum is 33.

The square root of 951981 is about 975.6951368127. The cubic root of 951981 is about 98.3730402380.

The spelling of 951981 in words is "nine hundred fifty-one thousand, nine hundred eighty-one".