61009631 has 4 divisors (see below), whose sum is σ = 61036200. Its totient is φ = 60983064.

The previous prime is 61009601. The next prime is 61009667. The reversal of 61009631 is 13690016.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61009631 is a prime.

It is a super-2 number, since 2×61009631² = 7444350149512322, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 61009631.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61009601) 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, 9476 + ... + 14553.

It is an arithmetic number, because the mean of its divisors is an integer number (15259050).

Almost surely, 2^61009631 is an apocalyptic number.

61009631 is a deficient number, since it is larger than the sum of its proper divisors (26569).

61009631 is a wasteful number, since it uses less digits than its factorization.

61009631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26568.

The product of its (nonzero) digits is 972, while the sum is 26.

The square root of 61009631 is about 7810.8662131674. The cubic root of 61009631 is about 393.6704343809.

Adding to 61009631 its reverse (13690016), we get a palindrome (74699647).

The spelling of 61009631 in words is "sixty-one million, nine thousand, six hundred thirty-one".