61215858 has 64 divisors (see below), whose sum is σ = 149351040. Its totient is φ = 18432000.

The previous prime is 61215851. The next prime is 61215883. The reversal of 61215858 is 85851216.

It is not an unprimeable number, because it can be changed into a prime (61215851) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 152458 + ... + 152858.

It is an arithmetic number, because the mean of its divisors is an integer number (2333610).

Almost surely, 2^61215858 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61215858, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (74675520).

61215858 is an abundant number, since it is smaller than the sum of its proper divisors (88135182).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

61215858 is a wasteful number, since it uses less digits than its factorization.

61215858 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 680 (or 674 counting only the distinct ones).

The product of its digits is 19200, while the sum is 36.

The square root of 61215858 is about 7824.0563648276. The cubic root of 61215858 is about 394.1135019609.

It can be divided in two parts, 612158 and 58, that added together give a palindrome (612216).

The spelling of 61215858 in words is "sixty-one million, two hundred fifteen thousand, eight hundred fifty-eight".