1221711 has 8 divisors (see below), whose sum is σ = 1635840. Its totient is φ = 811032.

The previous prime is 1221707. The next prime is 1221749. The reversal of 1221711 is 1171221.

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

It is not a de Polignac number, because 1221711 - 2² = 1221707 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221751) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 130 + ... + 1568.

It is an arithmetic number, because the mean of its divisors is an integer number (204480).

2^1221711 is an apocalyptic number.

1221711 is a deficient number, since it is larger than the sum of its proper divisors (414129).

1221711 is a wasteful number, since it uses less digits than its factorization.

1221711 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1725.

The product of its digits is 28, while the sum is 15.

The square root of 1221711 is about 1105.3103636536. The cubic root of 1221711 is about 106.9029019862.

Adding to 1221711 its reverse (1171221), we get a palindrome (2392932).

The spelling of 1221711 in words is "one million, two hundred twenty-one thousand, seven hundred eleven".