61210553557 has 4 divisors (see below), whose sum is σ = 61804830880. Its totient is φ = 60616276236.

The previous prime is 61210553519. The next prime is 61210553623. The reversal of 61210553557 is 75535501216.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61210553557 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61210557557) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 297138507 + ... + 297138712.

It is an arithmetic number, because the mean of its divisors is an integer number (15451207720).

Almost surely, 2^61210553557 is an apocalyptic number.

It is an amenable number.

61210553557 is a deficient number, since it is larger than the sum of its proper divisors (594277323).

61210553557 is a wasteful number, since it uses less digits than its factorization.

61210553557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 594277322.

The product of its (nonzero) digits is 157500, while the sum is 40.

The spelling of 61210553557 in words is "sixty-one billion, two hundred ten million, five hundred fifty-three thousand, five hundred fifty-seven".