61121391 has 8 divisors (see below), whose sum is σ = 81567024. Its totient is φ = 40711680.

The previous prime is 61121387. The next prime is 61121393. The reversal of 61121391 is 19312116.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 61121391 - 2² = 61121387 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61121393) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4720 + ... + 12021.

It is an arithmetic number, because the mean of its divisors is an integer number (10195878).

Almost surely, 2^61121391 is an apocalyptic number.

61121391 is a deficient number, since it is larger than the sum of its proper divisors (20445633).

61121391 is a wasteful number, since it uses less digits than its factorization.

61121391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17961.

The product of its digits is 324, while the sum is 24.

The square root of 61121391 is about 7818.0170759599. The cubic root of 61121391 is about 393.9106684193.

It can be divided in two parts, 6112 and 1391, that added together give a triangular number (7503 = T₁₂₂).

The spelling of 61121391 in words is "sixty-one million, one hundred twenty-one thousand, three hundred ninety-one".