61857997 has 2 divisors, whose sum is σ = 61857998. Its totient is φ = 61857996.

The previous prime is 61857979. The next prime is 61858001. The reversal of 61857997 is 79975816.

It is a happy number.

Together with previous prime (61857979) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 38180041 + 23677956 = 6179^2 + 4866^2 .

It is a cyclic number.

It is not a de Polignac number, because 61857997 - 2¹¹ = 61855949 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61857197) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30928998 + 30928999.

It is an arithmetic number, because the mean of its divisors is an integer number (30928999).

Almost surely, 2^61857997 is an apocalyptic number.

It is an amenable number.

61857997 is a deficient number, since it is larger than the sum of its proper divisors (1).

61857997 is an equidigital number, since it uses as much as digits as its factorization.

61857997 is an evil number, because the sum of its binary digits is even.

The product of its digits is 952560, while the sum is 52.

The square root of 61857997 is about 7864.9855053903. The cubic root of 61857997 is about 395.4867619806.

The spelling of 61857997 in words is "sixty-one million, eight hundred fifty-seven thousand, nine hundred ninety-seven".