1221502442 has 4 divisors (see below), whose sum is σ = 1832253666. Its totient is φ = 610751220.

The previous prime is 1221502439. The next prime is 1221502481. The reversal of 1221502442 is 2442051221.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 2442051221 = 2381 ⋅1025641.

It can be written as a sum of positive squares in only one way, i.e., 825930121 + 395572321 = 28739^2 + 19889^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 305375609 + ... + 305375612.

Almost surely, 2^1221502442 is an apocalyptic number.

1221502442 is a deficient number, since it is larger than the sum of its proper divisors (610751224).

1221502442 is an equidigital number, since it uses as much as digits as its factorization.

1221502442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 610751223.

The product of its (nonzero) digits is 1280, while the sum is 23.

The square root of 1221502442 is about 34949.9991702432. Note that the first 3 decimals coincide. The cubic root of 1221502442 is about 1068.9681851685.

Adding to 1221502442 its reverse (2442051221), we get a palindrome (3663553663).

The spelling of 1221502442 in words is "one billion, two hundred twenty-one million, five hundred two thousand, four hundred forty-two".