61881857 has 4 divisors (see below), whose sum is σ = 61931520. Its totient is φ = 61832196.

The previous prime is 61881821. The next prime is 61881863. The reversal of 61881857 is 75818816.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61881857 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61881557) 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 3 ways as a sum of consecutive naturals, for example, 22913 + ... + 25470.

It is an arithmetic number, because the mean of its divisors is an integer number (15482880).

Almost surely, 2^61881857 is an apocalyptic number.

It is an amenable number.

61881857 is a deficient number, since it is larger than the sum of its proper divisors (49663).

61881857 is a wasteful number, since it uses less digits than its factorization.

61881857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49662.

The product of its digits is 107520, while the sum is 44.

The square root of 61881857 is about 7866.5022087329. The cubic root of 61881857 is about 395.5376047796.

The spelling of 61881857 in words is "sixty-one million, eight hundred eighty-one thousand, eight hundred fifty-seven".