61220612501 has 2 divisors, whose sum is σ = 61220612502. Its totient is φ = 61220612500.

The previous prime is 61220612491. The next prime is 61220612543. The reversal of 61220612501 is 10521602216.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 54109738225 + 7110874276 = 232615^2 + 84326^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61220612501 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61220612561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30610306250 + 30610306251.

It is an arithmetic number, because the mean of its divisors is an integer number (30610306251).

Almost surely, 2^61220612501 is an apocalyptic number.

It is an amenable number.

61220612501 is a deficient number, since it is larger than the sum of its proper divisors (1).

61220612501 is an equidigital number, since it uses as much as digits as its factorization.

61220612501 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1440, while the sum is 26.

The spelling of 61220612501 in words is "sixty-one billion, two hundred twenty million, six hundred twelve thousand, five hundred one".