1689732457 has 4 divisors (see below), whose sum is σ = 1931122816. Its totient is φ = 1448342100.

The previous prime is 1689732449. The next prime is 1689732481. The reversal of 1689732457 is 7542379861.

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: 7542379861 = 227 ⋅33226343.

It is a cyclic number.

It is not a de Polignac number, because 1689732457 - 2³ = 1689732449 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1689732487) 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, 120695169 + ... + 120695182.

It is an arithmetic number, because the mean of its divisors is an integer number (482780704).

Almost surely, 2^1689732457 is an apocalyptic number.

It is an amenable number.

1689732457 is a deficient number, since it is larger than the sum of its proper divisors (241390359).

1689732457 is an equidigital number, since it uses as much as digits as its factorization.

1689732457 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 241390358.

The product of its digits is 2540160, while the sum is 52.

The square root of 1689732457 is about 41106.3554331931. The cubic root of 1689732457 is about 1191.0755657160.

The spelling of 1689732457 in words is "one billion, six hundred eighty-nine million, seven hundred thirty-two thousand, four hundred fifty-seven".