257220069 has 4 divisors (see below), whose sum is σ = 342960096. Its totient is φ = 171480044.

The previous prime is 257220059. The next prime is 257220079. The reversal of 257220069 is 960022752.

It is a happy number.

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 an interprime number because it is at equal distance from previous prime (257220059) and next prime (257220079).

It is a cyclic number.

It is not a de Polignac number, because 257220069 - 2¹⁶ = 257154533 is a prime.

It is a super-2 number, since 2×257220069² = 132324327792729522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257220059) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42870009 + ... + 42870014.

It is an arithmetic number, because the mean of its divisors is an integer number (85740024).

Almost surely, 2^257220069 is an apocalyptic number.

It is an amenable number.

257220069 is a deficient number, since it is larger than the sum of its proper divisors (85740027).

257220069 is an equidigital number, since it uses as much as digits as its factorization.

257220069 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85740026.

The product of its (nonzero) digits is 15120, while the sum is 33.

The square root of 257220069 is about 16038.0818366786. The cubic root of 257220069 is about 635.9675406677.

The spelling of 257220069 in words is "two hundred fifty-seven million, two hundred twenty thousand, sixty-nine".