1221501 has 16 divisors (see below), whose sum is σ = 1767744. Its totient is φ = 747264.

The previous prime is 1221499. The next prime is 1221503. The reversal of 1221501 is 1051221.

It is an interprime number because it is at equal distance from previous prime (1221499) and next prime (1221503).

It is not a de Polignac number, because 1221501 - 2¹ = 1221499 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221503) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1915 + ... + 2471.

It is an arithmetic number, because the mean of its divisors is an integer number (110484).

2^1221501 is an apocalyptic number.

It is an amenable number.

1221501 is a deficient number, since it is larger than the sum of its proper divisors (546243).

1221501 is a wasteful number, since it uses less digits than its factorization.

1221501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 620.

The product of its (nonzero) digits is 20, while the sum is 12.

The square root of 1221501 is about 1105.2153636283. The cubic root of 1221501 is about 106.8967764525.

Adding to 1221501 its reverse (1051221), we get a palindrome (2272722).

The spelling of 1221501 in words is "one million, two hundred twenty-one thousand, five hundred one".