61531351 has 4 divisors (see below), whose sum is σ = 70321552. Its totient is φ = 52741152.

The previous prime is 61531297. The next prime is 61531391. The reversal of 61531351 is 15313516.

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 61531351 - 2¹⁵ = 61498583 is a prime.

It is a super-2 number, since 2×61531351² = 7572214311770402, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61531391) 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, 4395090 + ... + 4395103.

It is an arithmetic number, because the mean of its divisors is an integer number (17580388).

Almost surely, 2^61531351 is an apocalyptic number.

61531351 is a deficient number, since it is larger than the sum of its proper divisors (8790201).

61531351 is an equidigital number, since it uses as much as digits as its factorization.

61531351 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8790200.

The product of its digits is 1350, while the sum is 25.

The square root of 61531351 is about 7844.1921827553. The cubic root of 61531351 is about 394.7894001001.

Adding to 61531351 its reverse (15313516), we get a palindrome (76844867).

The spelling of 61531351 in words is "sixty-one million, five hundred thirty-one thousand, three hundred fifty-one".