61261731 has 16 divisors (see below), whose sum is σ = 90960000. Its totient is φ = 40750344.

The previous prime is 61261721. The next prime is 61261741. The reversal of 61261731 is 13716216.

61261731 is a `hidden beast` number, since 6 + 12 + 617 + 31 = 666.

It is an interprime number because it is at equal distance from previous prime (61261721) and next prime (61261741).

It is not a de Polignac number, because 61261731 - 2⁹ = 61261219 is a prime.

It is a super-2 number, since 2×61261731² = 7505999370232722, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 61261695 and 61261704.

It is not an unprimeable number, because it can be changed into a prime (61261721) 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, 11200 + ... + 15746.

It is an arithmetic number, because the mean of its divisors is an integer number (5685000).

Almost surely, 2^61261731 is an apocalyptic number.

61261731 is a deficient number, since it is larger than the sum of its proper divisors (29698269).

61261731 is a wasteful number, since it uses less digits than its factorization.

61261731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5055 (or 5049 counting only the distinct ones).

The product of its digits is 1512, while the sum is 27.

The square root of 61261731 is about 7826.9873514654. The cubic root of 61261731 is about 394.2119222895.

Adding to 61261731 its reverse (13716216), we get a palindrome (74977947).

The spelling of 61261731 in words is "sixty-one million, two hundred sixty-one thousand, seven hundred thirty-one".