6561697219502 has 12 divisors (see below), whose sum is σ = 10170289293768. Its totient is φ = 3175014782700.

The previous prime is 6561697219489. The next prime is 6561697219507. The reversal of 6561697219502 is 2059127961656.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6561697219507) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1706995274 + ... + 1706999117.

It is an arithmetic number, because the mean of its divisors is an integer number (847524107814).

Almost surely, 2^{6561697219502} is an apocalyptic number.

6561697219502 is a gapful number since it is divisible by the number (62) formed by its first and last digit.

6561697219502 is a deficient number, since it is larger than the sum of its proper divisors (3608592074266).

6561697219502 is a wasteful number, since it uses less digits than its factorization.

6561697219502 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3413994455 (or 3413994424 counting only the distinct ones).

The product of its (nonzero) digits is 12247200, while the sum is 59.

Adding to 6561697219502 its sum of digits (59), we get a square (6561697219561 = 2561581²).

The spelling of 6561697219502 in words is "six trillion, five hundred sixty-one billion, six hundred ninety-seven million, two hundred nineteen thousand, five hundred two".