61644031 has 4 divisors (see below), whose sum is σ = 61954000. Its totient is φ = 61334064.

The previous prime is 61644029. The next prime is 61644041. The reversal of 61644031 is 13044616.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 61644031 - 2¹ = 61644029 is a prime.

It is a super-2 number, since 2×61644031² = 7599973115857922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 61643987 and 61644005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61644001) 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, 154686 + ... + 155083.

It is an arithmetic number, because the mean of its divisors is an integer number (15488500).

Almost surely, 2^61644031 is an apocalyptic number.

61644031 is a deficient number, since it is larger than the sum of its proper divisors (309969).

61644031 is a wasteful number, since it uses less digits than its factorization.

61644031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 309968.

The product of its (nonzero) digits is 1728, while the sum is 25.

The square root of 61644031 is about 7851.3712815024. The cubic root of 61644031 is about 395.0302407014.

Adding to 61644031 its reverse (13044616), we get a palindrome (74688647).

The spelling of 61644031 in words is "sixty-one million, six hundred forty-four thousand, thirty-one".