1221696 has 112 divisors (see below), whose sum is σ = 4145280. Its totient is φ = 345600.

The previous prime is 1221667. The next prime is 1221707. The reversal of 1221696 is 6961221.

It is a tau number, because it is divible by the number of its divisors (112).

It is a super-2 number, since 2×1221696² = 2985082232832, which contains 22 as substring.

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

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12046 + ... + 12146.

2^1221696 is an apocalyptic number.

1221696 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1221696, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2072640).

1221696 is an abundant number, since it is smaller than the sum of its proper divisors (2923584).

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

1221696 is a wasteful number, since it uses less digits than its factorization.

1221696 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129 (or 113 counting only the distinct ones).

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

The square root of 1221696 is about 1105.3035782083. The cubic root of 1221696 is about 106.9024644713.

The spelling of 1221696 in words is "one million, two hundred twenty-one thousand, six hundred ninety-six".