1642990 has 8 divisors (see below), whose sum is σ = 2957400. Its totient is φ = 657192.

The previous prime is 1642951. The next prime is 1642997. The reversal of 1642990 is 992461.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×1642990² = 5398832280200, which contains 22 as substring.

It is a plaindrome in base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1642997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 82140 + ... + 82159.

It is an arithmetic number, because the mean of its divisors is an integer number (369675).

2^1642990 is an apocalyptic number.

1642990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1642990 is a deficient number, since it is larger than the sum of its proper divisors (1314410).

1642990 is a wasteful number, since it uses less digits than its factorization.

1642990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 164306.

The product of its (nonzero) digits is 3888, while the sum is 31.

The square root of 1642990 is about 1281.7917147493. The cubic root of 1642990 is about 117.9989945332.

The spelling of 1642990 in words is "one million, six hundred forty-two thousand, nine hundred ninety".