61000000 has 98 divisors (see below), whose sum is σ = 153787094. Its totient is φ = 24000000.

The previous prime is 60999959. The next prime is 61000001. The reversal of 61000000 is 16.

It can be written as a sum of positive squares in 7 ways, for example, as 54405376 + 6594624 = 7376^2 + 2568^2 .

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61000001) by changing a digit.

It is a polite number, since it can be written in 13 ways as a sum of consecutive naturals, for example, 999970 + ... + 1000030.

Almost surely, 2^61000000 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (76893547).

61000000 is an abundant number, since it is smaller than the sum of its proper divisors (92787094).

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

61000000 is an frugal number, since it uses more digits than its factorization.

61000000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103 (or 68 counting only the distinct ones).

The product of its (nonzero) digits is 6, while the sum is 7.

The square root of 61000000 is about 7810.2496759067. The cubic root of 61000000 is about 393.6497183102.

Adding to 61000000 its reverse (16), we get a palindrome (61000016).

The spelling of 61000000 in words is "sixty-one million", and thus it is an aban number and an uban number.