1690738442 has 4 divisors (see below), whose sum is σ = 2536107666. Its totient is φ = 845369220.

The previous prime is 1690738433. The next prime is 1690738447. The reversal of 1690738442 is 2448370961.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 1266007561 + 424730881 = 35581^2 + 20609^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1690738393 and 1690738402.

It is not an unprimeable number, because it can be changed into a prime (1690738447) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 422684609 + ... + 422684612.

Almost surely, 2^1690738442 is an apocalyptic number.

1690738442 is a deficient number, since it is larger than the sum of its proper divisors (845369224).

1690738442 is an equidigital number, since it uses as much as digits as its factorization.

1690738442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 845369223.

The product of its (nonzero) digits is 290304, while the sum is 44.

The square root of 1690738442 is about 41118.5899806888. The cubic root of 1690738442 is about 1191.3118884234.

The spelling of 1690738442 in words is "one billion, six hundred ninety million, seven hundred thirty-eight thousand, four hundred forty-two".