661419 has 32 divisors (see below), whose sum is σ = 1140480. Its totient is φ = 374400.

The previous prime is 661417. The next prime is 661421. The reversal of 661419 is 914166.

It is an interprime number because it is at equal distance from previous prime (661417) and next prime (661421).

It is not a de Polignac number, because 661419 - 2¹ = 661417 is a prime.

It is a super-2 number, since 2×661419² = 874950187122, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

Its product of digits (1296) is a multiple of the sum of its prime divisors (162).

It is a junction number, because it is equal to n+sod(n) for n = 661392 and 661401.

It is not an unprimeable number, because it can be changed into a prime (661417) 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 in 31 ways as a sum of consecutive naturals, for example, 4984 + ... + 5114.

It is an arithmetic number, because the mean of its divisors is an integer number (35640).

2⁶⁶¹⁴¹⁹ is an apocalyptic number.

661419 is a deficient number, since it is larger than the sum of its proper divisors (479061).

661419 is a wasteful number, since it uses less digits than its factorization.

661419 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 168 (or 162 counting only the distinct ones).

The product of its digits is 1296, while the sum is 27.

The square root of 661419 is about 813.2767056789. The cubic root of 661419 is about 87.1282294589.

It can be divided in two parts, 66 and 1419, that added together give a triangular number (1485 = T₅₄).

The spelling of 661419 in words is "six hundred sixty-one thousand, four hundred nineteen".