61731251 has 2 divisors, whose sum is σ = 61731252. Its totient is φ = 61731250.

The previous prime is 61731223. The next prime is 61731269. The reversal of 61731251 is 15213716.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61731251 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 61731251.

It is not a weakly prime, because it can be changed into another prime (61731211) 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 as a sum of consecutive naturals, namely, 30865625 + 30865626.

It is an arithmetic number, because the mean of its divisors is an integer number (30865626).

Almost surely, 2^61731251 is an apocalyptic number.

61731251 is a deficient number, since it is larger than the sum of its proper divisors (1).

61731251 is an equidigital number, since it uses as much as digits as its factorization.

61731251 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1260, while the sum is 26.

The square root of 61731251 is about 7856.9237618803. The cubic root of 61731251 is about 395.2164620322.

Adding to 61731251 its reverse (15213716), we get a palindrome (76944967).

The spelling of 61731251 in words is "sixty-one million, seven hundred thirty-one thousand, two hundred fifty-one".