61851031 has 4 divisors (see below), whose sum is σ = 67473864. Its totient is φ = 56228200.

The previous prime is 61851017. The next prime is 61851037. The reversal of 61851031 is 13015816.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 61851031 - 2¹⁹ = 61326743 is a prime.

It is a super-2 number, since 2×61851031² = 7651100071525922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 61850987 and 61851005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61851037) 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 in 3 ways as a sum of consecutive naturals, for example, 2811400 + ... + 2811421.

It is an arithmetic number, because the mean of its divisors is an integer number (16868466).

Almost surely, 2^61851031 is an apocalyptic number.

61851031 is a deficient number, since it is larger than the sum of its proper divisors (5622833).

61851031 is a wasteful number, since it uses less digits than its factorization.

61851031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5622832.

The product of its (nonzero) digits is 720, while the sum is 25.

The square root of 61851031 is about 7864.5426440449. The cubic root of 61851031 is about 395.4719158042.

Adding to 61851031 its reverse (13015816), we get a palindrome (74866847).

The spelling of 61851031 in words is "sixty-one million, eight hundred fifty-one thousand, thirty-one".