1252777780 has 24 divisors (see below), whose sum is σ = 2631498408. Its totient is φ = 500984448.

The previous prime is 1252777763. The next prime is 1252777789. The reversal of 1252777780 is 877772521.

It can be written as a sum of positive squares in 4 ways, for example, as 346406544 + 906371236 = 18612^2 + 30106^2 .

It is a hoax number, since the sum of its digits (46) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 1252777780.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1252777789) 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, 150282 + ... + 158398.

It is an arithmetic number, because the mean of its divisors is an integer number (109645767).

Almost surely, 2^1252777780 is an apocalyptic number.

1252777780 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1252777780 is an abundant number, since it is smaller than the sum of its proper divisors (1378720628).

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

1252777780 is a wasteful number, since it uses less digits than its factorization.

1252777780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15843 (or 15841 counting only the distinct ones).

The product of its (nonzero) digits is 384160, while the sum is 46.

The square root of 1252777780 is about 35394.6010007176. The cubic root of 1252777780 is about 1078.0146940903.

The spelling of 1252777780 in words is "one billion, two hundred fifty-two million, seven hundred seventy-seven thousand, seven hundred eighty".