1251020481 has 4 divisors (see below), whose sum is σ = 1668027312. Its totient is φ = 834013652.

The previous prime is 1251020467. The next prime is 1251020509. The reversal of 1251020481 is 1840201521.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1251020481 - 2⁶ = 1251020417 is a prime.

It is a super-2 number, since 2×1251020481² = 3130104487762942722, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1251020581) 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, 208503411 + ... + 208503416.

It is an arithmetic number, because the mean of its divisors is an integer number (417006828).

Almost surely, 2^1251020481 is an apocalyptic number.

It is an amenable number.

1251020481 is a deficient number, since it is larger than the sum of its proper divisors (417006831).

1251020481 is an equidigital number, since it uses as much as digits as its factorization.

1251020481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 417006830.

The product of its (nonzero) digits is 640, while the sum is 24.

The square root of 1251020481 is about 35369.7678957609. The cubic root of 1251020481 is about 1077.5104065690.

The spelling of 1251020481 in words is "one billion, two hundred fifty-one million, twenty thousand, four hundred eighty-one".