1261551 has 8 divisors (see below), whose sum is σ = 1703680. Its totient is φ = 830232.

The previous prime is 1261549. The next prime is 1261567. The reversal of 1261551 is 1551621.

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

It is not a de Polignac number, because 1261551 - 2¹ = 1261549 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1261531) 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, 2425 + ... + 2898.

It is an arithmetic number, because the mean of its divisors is an integer number (212960).

2^1261551 is an apocalyptic number.

1261551 is a deficient number, since it is larger than the sum of its proper divisors (442129).

1261551 is an equidigital number, since it uses as much as digits as its factorization.

1261551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5405.

The product of its digits is 300, while the sum is 21.

The square root of 1261551 is about 1123.1878738662. The cubic root of 1261551 is about 108.0525293162.

The spelling of 1261551 in words is "one million, two hundred sixty-one thousand, five hundred fifty-one".