61640841 has 4 divisors (see below), whose sum is σ = 82187792. Its totient is φ = 41093892.

The previous prime is 61640837. The next prime is 61640867. The reversal of 61640841 is 14804616.

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 not a de Polignac number, because 61640841 - 2² = 61640837 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 61640799 and 61640808.

It is not an unprimeable number, because it can be changed into a prime (61640941) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10273471 + ... + 10273476.

It is an arithmetic number, because the mean of its divisors is an integer number (20546948).

Almost surely, 2^61640841 is an apocalyptic number.

It is an amenable number.

61640841 is a deficient number, since it is larger than the sum of its proper divisors (20546951).

61640841 is a wasteful number, since it uses less digits than its factorization.

61640841 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20546950.

The product of its (nonzero) digits is 4608, while the sum is 30.

The square root of 61640841 is about 7851.1681296480. The cubic root of 61640841 is about 395.0234264801.

It can be divided in two parts, 61640 and 841, that added together give a triangular number (62481 = T₃₅₃).

The spelling of 61640841 in words is "sixty-one million, six hundred forty thousand, eight hundred forty-one".