61613206214981 has 4 divisors (see below), whose sum is σ = 61613318750700. Its totient is φ = 61613093679264.

The previous prime is 61613206214977. The next prime is 61613206215059. The reversal of 61613206214981 is 18941260231616.

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

It can be written as a sum of positive squares in 2 ways, for example, as 29971343702881 + 31641862512100 = 5474609^2 + 5625110^2 .

It is a cyclic number.

It is not a de Polignac number, because 61613206214981 - 2² = 61613206214977 is a prime.

It is a super-2 number, since 2×61613206214981² (a number of 28 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61613206214081) 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, 55442576 + ... + 56542953.

It is an arithmetic number, because the mean of its divisors is an integer number (15403329687675).

Almost surely, 2^{61613206214981} is an apocalyptic number.

It is an amenable number.

61613206214981 is a deficient number, since it is larger than the sum of its proper divisors (112535719).

61613206214981 is a wasteful number, since it uses less digits than its factorization.

61613206214981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112535718.

The product of its (nonzero) digits is 746496, while the sum is 50.

The spelling of 61613206214981 in words is "sixty-one trillion, six hundred thirteen billion, two hundred six million, two hundred fourteen thousand, nine hundred eighty-one".