61616617977 has 4 divisors (see below), whose sum is σ = 82155490640. Its totient is φ = 41077745316.

The previous prime is 61616617949. The next prime is 61616617987. The reversal of 61616617977 is 77971661616.

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 not a de Polignac number, because 61616617977 - 2¹⁴ = 61616601593 is a prime.

It is a super-2 number, since 2×61616617977² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61616617987) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10269436327 + ... + 10269436332.

It is an arithmetic number, because the mean of its divisors is an integer number (20538872660).

Almost surely, 2^61616617977 is an apocalyptic number.

It is an amenable number.

61616617977 is a deficient number, since it is larger than the sum of its proper divisors (20538872663).

61616617977 is a wasteful number, since it uses less digits than its factorization.

61616617977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20538872662.

The product of its digits is 4000752, while the sum is 57.

The spelling of 61616617977 in words is "sixty-one billion, six hundred sixteen million, six hundred seventeen thousand, nine hundred seventy-seven".