61810290 has 80 divisors (see below), whose sum is σ = 167714712. Its totient is φ = 16333056.

The previous prime is 61810289. The next prime is 61810291. The reversal of 61810290 is 9201816.

It is an interprime number because it is at equal distance from previous prime (61810289) and next prime (61810291).

It can be written as a sum of positive squares in 4 ways, for example, as 38452401 + 23357889 = 6201^2 + 4833^2 .

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (61810291) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 110692 + ... + 111248.

Almost surely, 2^61810290 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61810290, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (83857356).

61810290 is an abundant number, since it is smaller than the sum of its proper divisors (105904422).

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

61810290 is a wasteful number, since it uses less digits than its factorization.

61810290 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 713 (or 704 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The square root of 61810290 is about 7861.9520476787. The cubic root of 61810290 is about 395.3850648659.

The spelling of 61810290 in words is "sixty-one million, eight hundred ten thousand, two hundred ninety".