1553506 has 4 divisors (see below), whose sum is σ = 2330262. Its totient is φ = 776752.

The previous prime is 1553479. The next prime is 1553507. The reversal of 1553506 is 6053551.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 6053551 = 7 ⋅864793.

It can be written as a sum of positive squares in only one way, i.e., 1550025 + 3481 = 1245^2 + 59^2 .

It is not an unprimeable number, because it can be changed into a prime (1553507) 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 as a sum of consecutive naturals, namely, 388375 + ... + 388378.

2^1553506 is an apocalyptic number.

1553506 is a deficient number, since it is larger than the sum of its proper divisors (776756).

1553506 is an equidigital number, since it uses as much as digits as its factorization.

1553506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 776755.

The product of its (nonzero) digits is 2250, while the sum is 25.

The square root of 1553506 is about 1246.3972079558. The cubic root of 1553506 is about 115.8166445371.

The spelling of 1553506 in words is "one million, five hundred fifty-three thousand, five hundred six".