61861813 has 8 divisors (see below), whose sum is σ = 66917088. Its totient is φ = 56848944.

The previous prime is 61861801. The next prime is 61861841. The reversal of 61861813 is 31816816.

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

It is a cyclic number.

It is not a de Polignac number, because 61861813 - 2⁵ = 61861781 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61861883) 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, 7531 + ... + 13432.

It is an arithmetic number, because the mean of its divisors is an integer number (8364636).

Almost surely, 2^61861813 is an apocalyptic number.

It is an amenable number.

61861813 is a deficient number, since it is larger than the sum of its proper divisors (5055275).

61861813 is a wasteful number, since it uses less digits than its factorization.

61861813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21203.

The product of its digits is 6912, while the sum is 34.

The square root of 61861813 is about 7865.2280958660. The cubic root of 61861813 is about 395.4948942972.

The spelling of 61861813 in words is "sixty-one million, eight hundred sixty-one thousand, eight hundred thirteen".