1521994 has 4 divisors (see below), whose sum is σ = 2282994. Its totient is φ = 760996.

The previous prime is 1521991. The next prime is 1522009. The reversal of 1521994 is 4991251.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 4991251 = 17 ⋅293603.

It can be written as a sum of positive squares in only one way, i.e., 1471369 + 50625 = 1213^2 + 225^2 .

It is not an unprimeable number, because it can be changed into a prime (1521991) 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, 380497 + ... + 380500.

2^1521994 is an apocalyptic number.

1521994 is a deficient number, since it is larger than the sum of its proper divisors (761000).

1521994 is an equidigital number, since it uses as much as digits as its factorization.

1521994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 760999.

The product of its digits is 3240, while the sum is 31.

The square root of 1521994 is about 1233.6912093389. The cubic root of 1521994 is about 115.0281972444.

It can be divided in two parts, 15219 and 94, that multiplied together give a triangular number (1430586 = T₁₆₉₁).

The spelling of 1521994 in words is "one million, five hundred twenty-one thousand, nine hundred ninety-four".