1688214261 has 4 divisors (see below), whose sum is σ = 2250952352. Its totient is φ = 1125476172.

The previous prime is 1688214251. The next prime is 1688214263. The reversal of 1688214261 is 1624128861.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1624128861 = 3 ⋅541376287.

It is not a de Polignac number, because 1688214261 - 2⁹ = 1688213749 is a prime.

It is a super-2 number, since 2×1688214261² = 5700134782087552242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1688214263) 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, 281369041 + ... + 281369046.

It is an arithmetic number, because the mean of its divisors is an integer number (562738088).

Almost surely, 2^1688214261 is an apocalyptic number.

It is an amenable number.

1688214261 is a deficient number, since it is larger than the sum of its proper divisors (562738091).

1688214261 is an equidigital number, since it uses as much as digits as its factorization.

1688214261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 562738090.

The product of its digits is 36864, while the sum is 39.

The square root of 1688214261 is about 41087.8846011814. The cubic root of 1688214261 is about 1190.7187384179.

The spelling of 1688214261 in words is "one billion, six hundred eighty-eight million, two hundred fourteen thousand, two hundred sixty-one".