61490191 has 4 divisors (see below), whose sum is σ = 70274512. Its totient is φ = 52705872.

The previous prime is 61490153. The next prime is 61490227. The reversal of 61490191 is 19109416.

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 61490191 - 2⁹ = 61489679 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61490131) 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, 4392150 + ... + 4392163.

It is an arithmetic number, because the mean of its divisors is an integer number (17568628).

Almost surely, 2^61490191 is an apocalyptic number.

61490191 is a deficient number, since it is larger than the sum of its proper divisors (8784321).

61490191 is an equidigital number, since it uses as much as digits as its factorization.

61490191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8784320.

The product of its (nonzero) digits is 1944, while the sum is 31.

The square root of 61490191 is about 7841.5681467421. The cubic root of 61490191 is about 394.7013519965.

The spelling of 61490191 in words is "sixty-one million, four hundred ninety thousand, one hundred ninety-one".