1261887151 has 6 divisors (see below), whose sum is σ = 1467909600. Its totient is φ = 1081617516.

The previous prime is 1261887139. The next prime is 1261887163. The reversal of 1261887151 is 1517881621.

It is an interprime number because it is at equal distance from previous prime (1261887139) and next prime (1261887163).

It is not a de Polignac number, because 1261887151 - 2¹⁵ = 1261854383 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 (1261887131) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 12876351 + ... + 12876448.

It is an arithmetic number, because the mean of its divisors is an integer number (244651600).

Almost surely, 2^1261887151 is an apocalyptic number.

1261887151 is a deficient number, since it is larger than the sum of its proper divisors (206022449).

1261887151 is an equidigital number, since it uses as much as digits as its factorization.

1261887151 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25752813 (or 25752806 counting only the distinct ones).

The product of its digits is 26880, while the sum is 40.

The square root of 1261887151 is about 35523.0509810179. The cubic root of 1261887151 is about 1080.6212563590.

The spelling of 1261887151 in words is "one billion, two hundred sixty-one million, eight hundred eighty-seven thousand, one hundred fifty-one".