1390021 has 8 divisors (see below), whose sum is σ = 1476000. Its totient is φ = 1305360.

The previous prime is 1390019. The next prime is 1390027. The reversal of 1390021 is 1200931.

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

It is a cyclic number.

It is not a de Polignac number, because 1390021 - 2¹ = 1390019 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1389977 and 1390004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1390027) 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 7 ways as a sum of consecutive naturals, for example, 2586 + ... + 3076.

It is an arithmetic number, because the mean of its divisors is an integer number (184500).

2^1390021 is an apocalyptic number.

It is an amenable number.

1390021 is a deficient number, since it is larger than the sum of its proper divisors (85979).

1390021 is a wasteful number, since it uses less digits than its factorization.

1390021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 659.

The product of its (nonzero) digits is 54, while the sum is 16.

The square root of 1390021 is about 1178.9915182053. The cubic root of 1390021 is about 111.6024650132.

Adding to 1390021 its reverse (1200931), we get a palindrome (2590952).

The spelling of 1390021 in words is "one million, three hundred ninety thousand, twenty-one".