61451491 has 16 divisors (see below), whose sum is σ = 66044160. Its totient is φ = 57011040.

The previous prime is 61451479. The next prime is 61451519. The reversal of 61451491 is 19415416.

It is a cyclic number.

It is not a de Polignac number, because 61451491 - 2¹⁷ = 61320419 is a prime.

It is a super-2 number, since 2×61451491² = 7552571492246162, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61451891) 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, 339421 + ... + 339601.

It is an arithmetic number, because the mean of its divisors is an integer number (4127760).

Almost surely, 2^61451491 is an apocalyptic number.

61451491 is a deficient number, since it is larger than the sum of its proper divisors (4592669).

61451491 is a wasteful number, since it uses less digits than its factorization.

61451491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 474.

The product of its digits is 4320, while the sum is 31.

The square root of 61451491 is about 7839.1001396844. The cubic root of 61451491 is about 394.6185303967.

The spelling of 61451491 in words is "sixty-one million, four hundred fifty-one thousand, four hundred ninety-one".