61521457547 has 16 divisors (see below), whose sum is σ = 67497408000. Its totient is φ = 55609741440.

The previous prime is 61521457519. The next prime is 61521457549. The reversal of 61521457547 is 74575412516.

It is not a de Polignac number, because 61521457547 - 2¹² = 61521453451 is a prime.

It is not an unprimeable number, because it can be changed into a prime (61521457549) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3508979 + ... + 3526467.

It is an arithmetic number, because the mean of its divisors is an integer number (4218588000).

Almost surely, 2^61521457547 is an apocalyptic number.

61521457547 is a deficient number, since it is larger than the sum of its proper divisors (5975950453).

61521457547 is a wasteful number, since it uses less digits than its factorization.

61521457547 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19306.

The product of its digits is 1176000, while the sum is 47.

The spelling of 61521457547 in words is "sixty-one billion, five hundred twenty-one million, four hundred fifty-seven thousand, five hundred forty-seven".