61816851 has 20 divisors (see below), whose sum is σ = 93865024. Its totient is φ = 40532400.

The previous prime is 61816849. The next prime is 61816871. The reversal of 61816851 is 15861816.

It is not a de Polignac number, because 61816851 - 2¹ = 61816849 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61816831) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 1315 + ... + 11196.

Almost surely, 2^61816851 is an apocalyptic number.

61816851 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

61816851 is a deficient number, since it is larger than the sum of its proper divisors (32048173).

61816851 is a wasteful number, since it uses less digits than its factorization.

61816851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12584 (or 12575 counting only the distinct ones).

The product of its digits is 11520, while the sum is 36.

The square root of 61816851 is about 7862.3692993906. The cubic root of 61816851 is about 395.3990540664.

The spelling of 61816851 in words is "sixty-one million, eight hundred sixteen thousand, eight hundred fifty-one".