61836409 has 4 divisors (see below), whose sum is σ = 61865104. Its totient is φ = 61807716.

The previous prime is 61836407. The next prime is 61836419. The reversal of 61836409 is 90463816.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 61836409 - 2¹ = 61836407 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61836403) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10827 + ... + 15520.

It is an arithmetic number, because the mean of its divisors is an integer number (15466276).

Almost surely, 2^61836409 is an apocalyptic number.

It is an amenable number.

61836409 is a deficient number, since it is larger than the sum of its proper divisors (28695).

61836409 is a wasteful number, since it uses less digits than its factorization.

61836409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28694.

The product of its (nonzero) digits is 31104, while the sum is 37.

The square root of 61836409 is about 7863.6129736909. The cubic root of 61836409 is about 395.4407492739.

The spelling of 61836409 in words is "sixty-one million, eight hundred thirty-six thousand, four hundred nine".