661230211526 has 16 divisors (see below), whose sum is σ = 1018987707696. Its totient is φ = 321573532896.

The previous prime is 661230211507. The next prime is 661230211561. The reversal of 661230211526 is 625112032166.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1246376 + ... + 1695851.

It is an arithmetic number, because the mean of its divisors is an integer number (63686731731).

Almost surely, 2^661230211526 is an apocalyptic number.

661230211526 is a deficient number, since it is larger than the sum of its proper divisors (357757496170).

661230211526 is a wasteful number, since it uses less digits than its factorization.

661230211526 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2945303.

The product of its (nonzero) digits is 25920, while the sum is 35.

The spelling of 661230211526 in words is "six hundred sixty-one billion, two hundred thirty million, two hundred eleven thousand, five hundred twenty-six".