1221361071 has 16 divisors (see below), whose sum is σ = 1925299200. Its totient is φ = 673854048.

The previous prime is 1221361067. The next prime is 1221361079. The reversal of 1221361071 is 1701631221.

It is not a de Polignac number, because 1221361071 - 2² = 1221361067 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221361079) 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, 1002151 + ... + 1003368.

It is an arithmetic number, because the mean of its divisors is an integer number (120331200).

Almost surely, 2^1221361071 is an apocalyptic number.

1221361071 is a deficient number, since it is larger than the sum of its proper divisors (703938129).

1221361071 is a wasteful number, since it uses less digits than its factorization.

1221361071 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2005558.

The product of its (nonzero) digits is 504, while the sum is 24.

The square root of 1221361071 is about 34947.9766367096. The cubic root of 1221361071 is about 1068.9269444454.

Adding to 1221361071 its reverse (1701631221), we get a palindrome (2922992292).

The spelling of 1221361071 in words is "one billion, two hundred twenty-one million, three hundred sixty-one thousand, seventy-one".