61818861 has 16 divisors (see below), whose sum is σ = 89159616. Its totient is φ = 37873536.

The previous prime is 61818859. The next prime is 61818863. The reversal of 61818861 is 16881816.

It is an interprime number because it is at equal distance from previous prime (61818859) and next prime (61818863).

It is not a de Polignac number, because 61818861 - 2¹ = 61818859 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61818863) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5686 + ... + 12488.

It is an arithmetic number, because the mean of its divisors is an integer number (5572476).

Almost surely, 2^61818861 is an apocalyptic number.

It is an amenable number.

61818861 is a deficient number, since it is larger than the sum of its proper divisors (27340755).

61818861 is a wasteful number, since it uses less digits than its factorization.

61818861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7052.

The product of its digits is 18432, while the sum is 39.

The square root of 61818861 is about 7862.4971224160. The cubic root of 61818861 is about 395.4033395402.

The spelling of 61818861 in words is "sixty-one million, eight hundred eighteen thousand, eight hundred sixty-one".