61857213 has 8 divisors (see below), whose sum is σ = 89974176. Its totient is φ = 37489200.

The previous prime is 61857199. The next prime is 61857227. The reversal of 61857213 is 31275816.

It is an interprime number because it is at equal distance from previous prime (61857199) and next prime (61857227).

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

It is not a de Polignac number, because 61857213 - 2⁴ = 61857197 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33), and also a Moran number because the ratio is a prime number: 1874461 = 61857213 / (6 + 1 + 8 + 5 + 7 + 2 + 1 + 3).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61857253) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 937198 + ... + 937263.

It is an arithmetic number, because the mean of its divisors is an integer number (11246772).

Almost surely, 2^61857213 is an apocalyptic number.

It is an amenable number.

61857213 is a deficient number, since it is larger than the sum of its proper divisors (28116963).

61857213 is a wasteful number, since it uses less digits than its factorization.

61857213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1874475.

The product of its digits is 10080, while the sum is 33.

The square root of 61857213 is about 7864.9356640725. The cubic root of 61857213 is about 395.4850911487.

The spelling of 61857213 in words is "sixty-one million, eight hundred fifty-seven thousand, two hundred thirteen".