1221670 has 8 divisors (see below), whose sum is σ = 2199024. Its totient is φ = 488664.

The previous prime is 1221667. The next prime is 1221707. The reversal of 1221670 is 761221.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 61074 + ... + 61093.

It is an arithmetic number, because the mean of its divisors is an integer number (274878).

2^1221670 is an apocalyptic number.

1221670 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1221670 is a deficient number, since it is larger than the sum of its proper divisors (977354).

1221670 is a wasteful number, since it uses less digits than its factorization.

1221670 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122174.

The product of its (nonzero) digits is 168, while the sum is 19.

The square root of 1221670 is about 1105.2918166711. The cubic root of 1221670 is about 106.9017061038.

Adding to 1221670 its reverse (761221), we get a palindrome (1982891).

It can be divided in two parts, 1221 and 670, that added together give a triangular number (1891 = T₆₁).

The spelling of 1221670 in words is "one million, two hundred twenty-one thousand, six hundred seventy".