1421660 has 24 divisors (see below), whose sum is σ = 3083136. Its totient is φ = 550080.

The previous prime is 1421647. The next prime is 1421663. The reversal of 1421660 is 661241.

1421660 = T₁₈₇ + T₁₈₈ + ... + T₂₄₆.

It is a happy number.

It is a super-2 number, since 2×1421660² = 4042234311200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1421663) 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 7 ways as a sum of consecutive naturals, for example, 527 + ... + 1766.

It is an arithmetic number, because the mean of its divisors is an integer number (128464).

2^1421660 is an apocalyptic number.

1421660 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1421660 is an abundant number, since it is smaller than the sum of its proper divisors (1661476).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1421660 is a wasteful number, since it uses less digits than its factorization.

1421660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2333 (or 2331 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 1421660 is about 1192.3338458670. Note that the first 3 decimals coincide. The cubic root of 1421660 is about 112.4428681105.

The spelling of 1421660 in words is "one million, four hundred twenty-one thousand, six hundred sixty".