61997897 has 8 divisors (see below), whose sum is σ = 66836616. Its totient is φ = 57169152.

The previous prime is 61997891. The next prime is 61997917. The reversal of 61997897 is 79879916.

It can be written as a sum of positive squares in 4 ways, for example, as 27081616 + 34916281 = 5204^2 + 5909^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 61997897 - 2⁸ = 61997641 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61997891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15023 + ... + 18699.

It is an arithmetic number, because the mean of its divisors is an integer number (8354577).

Almost surely, 2^61997897 is an apocalyptic number.

It is an amenable number.

61997897 is a deficient number, since it is larger than the sum of its proper divisors (4838719).

61997897 is a wasteful number, since it uses less digits than its factorization.

61997897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4987.

The product of its digits is 1714608, while the sum is 56.

The square root of 61997897 is about 7873.8743322458. The cubic root of 61997897 is about 395.7846859464.

The spelling of 61997897 in words is "sixty-one million, nine hundred ninety-seven thousand, eight hundred ninety-seven".