61278753506 has 4 divisors (see below), whose sum is σ = 91918130262. Its totient is φ = 30639376752.

The previous prime is 61278753451. The next prime is 61278753511. The reversal of 61278753506 is 60535787216.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 52973165281 + 8305588225 = 230159^2 + 91135^2 .

It is a Curzon 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 as a sum of consecutive naturals, namely, 15319688375 + ... + 15319688378.

Almost surely, 2^61278753506 is an apocalyptic number.

61278753506 is a deficient number, since it is larger than the sum of its proper divisors (30639376756).

61278753506 is a wasteful number, since it uses less digits than its factorization.

61278753506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30639376755.

The product of its (nonzero) digits is 2116800, while the sum is 50.

The spelling of 61278753506 in words is "sixty-one billion, two hundred seventy-eight million, seven hundred fifty-three thousand, five hundred six".