257223981 has 24 divisors (see below), whose sum is σ = 400898784. Its totient is φ = 146270880.

The previous prime is 257223971. The next prime is 257224001. The reversal of 257223981 is 189322752.

It is not a de Polignac number, because 257223981 - 2⁶ = 257223917 is a prime.

It is a super-2 number, since 2×257223981² = 132328352802976722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257223931) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 26871 + ... + 35163.

It is an arithmetic number, because the mean of its divisors is an integer number (16704116).

Almost surely, 2^257223981 is an apocalyptic number.

257223981 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

257223981 is a deficient number, since it is larger than the sum of its proper divisors (143674803).

257223981 is a wasteful number, since it uses less digits than its factorization.

257223981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8521 (or 8514 counting only the distinct ones).

The product of its digits is 60480, while the sum is 39.

The square root of 257223981 is about 16038.2037959368. The cubic root of 257223981 is about 635.9707647453.

The spelling of 257223981 in words is "two hundred fifty-seven million, two hundred twenty-three thousand, nine hundred eighty-one".