1220542402 has 4 divisors (see below), whose sum is σ = 1830813606. Its totient is φ = 610271200.

The previous prime is 1220542397. The next prime is 1220542423. The reversal of 1220542402 is 2042450221.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 862538161 + 358004241 = 29369^2 + 18921^2 .

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 305135599 + ... + 305135602.

Almost surely, 2^1220542402 is an apocalyptic number.

1220542402 is a deficient number, since it is larger than the sum of its proper divisors (610271204).

1220542402 is an equidigital number, since it uses as much as digits as its factorization.

1220542402 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 610271203.

The product of its (nonzero) digits is 1280, while the sum is 22.

The square root of 1220542402 is about 34936.2619923769. The cubic root of 1220542402 is about 1068.6880598737.

Adding to 1220542402 its reverse (2042450221), we get a palindrome (3262992623).

The spelling of 1220542402 in words is "one billion, two hundred twenty million, five hundred forty-two thousand, four hundred two".