1021401 has 6 divisors (see below), whose sum is σ = 1475370. Its totient is φ = 680928.

The previous prime is 1021387. The next prime is 1021403. The reversal of 1021401 is 1041201.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 632025 + 389376 = 795^2 + 624^2 .

It is not a de Polignac number, because 1021401 - 2⁵ = 1021369 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9), and also a Moran number because the ratio is a prime number: 113489 = 1021401 / (1 + 0 + 2 + 1 + 4 + 0 + 1).

1021401 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1021403) 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 5 ways as a sum of consecutive naturals, for example, 56736 + ... + 56753.

It is an arithmetic number, because the mean of its divisors is an integer number (245895).

2^1021401 is an apocalyptic number.

It is an amenable number.

1021401 is a deficient number, since it is larger than the sum of its proper divisors (453969).

1021401 is a wasteful number, since it uses less digits than its factorization.

1021401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 113495 (or 113492 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 1021401 is about 1010.6438541841. The cubic root of 1021401 is about 100.7083374012.

Adding to 1021401 its reverse (1041201), we get a palindrome (2062602).

The spelling of 1021401 in words is "one million, twenty-one thousand, four hundred one".