1997401 has 4 divisors (see below), whose sum is σ = 2282752. Its totient is φ = 1712052.

The previous prime is 1997351. The next prime is 1997407. The reversal of 1997401 is 1047991.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1047991 = 7 ⋅149713.

It is a cyclic number.

It is not a de Polignac number, because 1997401 - 2¹¹ = 1995353 is a prime.

It is a super-2 number, since 2×1997401² = 7979221509602, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1997407) 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 3 ways as a sum of consecutive naturals, for example, 142665 + ... + 142678.

It is an arithmetic number, because the mean of its divisors is an integer number (570688).

2^1997401 is an apocalyptic number.

It is an amenable number.

1997401 is a deficient number, since it is larger than the sum of its proper divisors (285351).

1997401 is an equidigital number, since it uses as much as digits as its factorization.

1997401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 285350.

The product of its (nonzero) digits is 2268, while the sum is 31.

The square root of 1997401 is about 1413.2943783940. The cubic root of 1997401 is about 125.9375057519.

The spelling of 1997401 in words is "one million, nine hundred ninety-seven thousand, four hundred one".