61357831 has 4 divisors (see below), whose sum is σ = 61381152. Its totient is φ = 61334512.

The previous prime is 61357819. The next prime is 61357843. The reversal of 61357831 is 13875316.

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

It is an interprime number because it is at equal distance from previous prime (61357819) and next prime (61357843).

It is a cyclic number.

It is not a de Polignac number, because 61357831 - 2⁹ = 61357319 is a prime.

It is a super-2 number, since 2×61357831² = 7529566850049122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61357871) 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, 7126 + ... + 13171.

It is an arithmetic number, because the mean of its divisors is an integer number (15345288).

Almost surely, 2^61357831 is an apocalyptic number.

61357831 is a deficient number, since it is larger than the sum of its proper divisors (23321).

61357831 is a wasteful number, since it uses less digits than its factorization.

61357831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23320.

The product of its digits is 15120, while the sum is 34.

The square root of 61357831 is about 7833.1239617409. The cubic root of 61357831 is about 394.4179452732.

The spelling of 61357831 in words is "sixty-one million, three hundred fifty-seven thousand, eight hundred thirty-one".