1561401 has 24 divisors (see below), whose sum is σ = 2483520. Its totient is φ = 940896.

The previous prime is 1561393. The next prime is 1561421. The reversal of 1561401 is 1041651.

It is not a de Polignac number, because 1561401 - 2³ = 1561393 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1561421) 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, 3735 + ... + 4131.

It is an arithmetic number, because the mean of its divisors is an integer number (103480).

2^1561401 is an apocalyptic number.

It is an amenable number.

1561401 is a deficient number, since it is larger than the sum of its proper divisors (922119).

1561401 is a wasteful number, since it uses less digits than its factorization.

1561401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 445 (or 442 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 18.

The square root of 1561401 is about 1249.5603226735. The cubic root of 1561401 is about 116.0125085600.

It can be divided in two parts, 15 and 61401, that added together give a palindrome (61416).

The spelling of 1561401 in words is "one million, five hundred sixty-one thousand, four hundred one".