61309899 has 16 divisors (see below), whose sum is σ = 103805440. Its totient is φ = 35034120.

The previous prime is 61309889. The next prime is 61309921. The reversal of 61309899 is 99890316.

It is not a de Polignac number, because 61309899 - 2¹³ = 61301707 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 (61309879) 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, 162007 + ... + 162384.

It is an arithmetic number, because the mean of its divisors is an integer number (6487840).

Almost surely, 2^61309899 is an apocalyptic number.

61309899 is a deficient number, since it is larger than the sum of its proper divisors (42495541).

61309899 is a wasteful number, since it uses less digits than its factorization.

61309899 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 324407 (or 324401 counting only the distinct ones).

The product of its (nonzero) digits is 104976, while the sum is 45.

The square root of 61309899 is about 7830.0637928436. The cubic root of 61309899 is about 394.3152136651.

The spelling of 61309899 in words is "sixty-one million, three hundred nine thousand, eight hundred ninety-nine".