1690506387 has 24 divisors (see below), whose sum is σ = 2518551360. Its totient is φ = 1092076800.

The previous prime is 1690506341. The next prime is 1690506407. The reversal of 1690506387 is 7836050961.

It is a happy number.

1690506387 is a `hidden beast` number, since 1 + 6 + 9 + 0 + 5 + 0 + 638 + 7 = 666.

It is not a de Polignac number, because 1690506387 - 2¹⁰ = 1690505363 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1690506487) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 22939 + ... + 62507.

It is an arithmetic number, because the mean of its divisors is an integer number (104939640).

Almost surely, 2^1690506387 is an apocalyptic number.

1690506387 is a deficient number, since it is larger than the sum of its proper divisors (828044973).

1690506387 is a wasteful number, since it uses less digits than its factorization.

1690506387 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39723 (or 39720 counting only the distinct ones).

The product of its (nonzero) digits is 272160, while the sum is 45.

The square root of 1690506387 is about 41115.7681066522. The cubic root of 1690506387 is about 1191.2573831410.

The spelling of 1690506387 in words is "one billion, six hundred ninety million, five hundred six thousand, three hundred eighty-seven".