1221023521502 has 16 divisors (see below), whose sum is σ = 1838844184320. Its totient is φ = 608075931648.

The previous prime is 1221023521441. The next prime is 1221023521517. The reversal of 1221023521502 is 2051253201221.

It is a happy number.

It is a super-2 number, since 2×1221023521502² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5314838 + ... + 5539814.

It is an arithmetic number, because the mean of its divisors is an integer number (114927761520).

Almost surely, 2^{1221023521502} is an apocalyptic number.

1221023521502 is a deficient number, since it is larger than the sum of its proper divisors (617820662818).

1221023521502 is a wasteful number, since it uses less digits than its factorization.

1221023521502 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 235795.

The product of its (nonzero) digits is 2400, while the sum is 26.

Adding to 1221023521502 its reverse (2051253201221), we get a palindrome (3272276722723).

The spelling of 1221023521502 in words is "one trillion, two hundred twenty-one billion, twenty-three million, five hundred twenty-one thousand, five hundred two".