1261634250 has 32 divisors (see below), whose sum is σ = 3149040960. Its totient is φ = 336435600.

The previous prime is 1261634239. The next prime is 1261634261. The reversal of 1261634250 is 524361621.

It is an interprime number because it is at equal distance from previous prime (1261634239) and next prime (1261634261).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 840340 + ... + 841839.

It is an arithmetic number, because the mean of its divisors is an integer number (98407530).

Almost surely, 2^1261634250 is an apocalyptic number.

1261634250 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1261634250 is an abundant number, since it is smaller than the sum of its proper divisors (1887406710).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1261634250 is a wasteful number, since it uses less digits than its factorization.

1261634250 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1682199 (or 1682189 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 30.

The square root of 1261634250 is about 35519.4911281116. The cubic root of 1261634250 is about 1080.5490606651.

Adding to 1261634250 its reverse (524361621), we get a palindrome (1785995871).

The spelling of 1261634250 in words is "one billion, two hundred sixty-one million, six hundred thirty-four thousand, two hundred fifty".