61223551515 has 240 divisors, whose sum is σ = 135054295200. Its totient is φ = 26383408128.

The previous prime is 61223551471. The next prime is 61223551537. The reversal of 61223551515 is 51515532216.

61223551515 is a `hidden beast` number, since 6 + 122 + 3 + 5 + 515 + 15 = 666.

It is not a de Polignac number, because 61223551515 - 2¹³ = 61223543323 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 61223551515.

It is an unprimeable number.

It is a polite number, since it can be written in 239 ways as a sum of consecutive naturals, for example, 149690631 + ... + 149691039.

It is an arithmetic number, because the mean of its divisors is an integer number (562726230).

Almost surely, 2^61223551515 is an apocalyptic number.

61223551515 is an abundant number, since it is smaller than the sum of its proper divisors (73830743685).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

61223551515 is a wasteful number, since it uses less digits than its factorization.

61223551515 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 856 (or 840 counting only the distinct ones).

The product of its digits is 45000, while the sum is 36.

The spelling of 61223551515 in words is "sixty-one billion, two hundred twenty-three million, five hundred fifty-one thousand, five hundred fifteen".