61564140121 has 16 divisors (see below), whose sum is σ = 68265114048. Its totient is φ = 55049702400.

The previous prime is 61564140109. The next prime is 61564140133. The reversal of 61564140121 is 12104146516.

It is an interprime number because it is at equal distance from previous prime (61564140109) and next prime (61564140133).

It is not a de Polignac number, because 61564140121 - 2²⁹ = 61027269209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61564144121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 433941 + ... + 558061.

It is an arithmetic number, because the mean of its divisors is an integer number (4266569628).

Almost surely, 2^61564140121 is an apocalyptic number.

It is an amenable number.

61564140121 is a deficient number, since it is larger than the sum of its proper divisors (6700973927).

61564140121 is a wasteful number, since it uses less digits than its factorization.

61564140121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124872.

The product of its (nonzero) digits is 5760, while the sum is 31.

Adding to 61564140121 its reverse (12104146516), we get a palindrome (73668286637).

The spelling of 61564140121 in words is "sixty-one billion, five hundred sixty-four million, one hundred forty thousand, one hundred twenty-one".