1216621053 has 48 divisors (see below), whose sum is σ = 1938081600. Its totient is φ = 760492800.

The previous prime is 1216621051. The next prime is 1216621057. The reversal of 1216621053 is 3501266121.

It is not a de Polignac number, because 1216621053 - 2¹ = 1216621051 is a prime.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216621051) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 465013 + ... + 467621.

It is an arithmetic number, because the mean of its divisors is an integer number (40376700).

Almost surely, 2^1216621053 is an apocalyptic number.

It is an amenable number.

1216621053 is a deficient number, since it is larger than the sum of its proper divisors (721460547).

1216621053 is a wasteful number, since it uses less digits than its factorization.

1216621053 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2744 (or 2732 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 1216621053 is about 34880.0953697091. The cubic root of 1216621053 is about 1067.5423411550.

Adding to 1216621053 its reverse (3501266121), we get a palindrome (4717887174).

The spelling of 1216621053 in words is "one billion, two hundred sixteen million, six hundred twenty-one thousand, fifty-three".