3901557780 has 120 divisors (see below), whose sum is σ = 12348223272. Its totient is φ = 1031159808.

The previous prime is 3901557767. The next prime is 3901557797. The reversal of 3901557780 is 877551093.

3901557780 is a `hidden beast` number, since 3 + 90 + 1 + 557 + 7 + 8 + 0 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 63011844 + 3838545936 = 7938^2 + 61956^2 .

It is a super-2 number, since 2×3901557780² = 30444306221357056800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 172404 + ... + 193716.

Almost surely, 2^3901557780 is an apocalyptic number.

3901557780 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 3901557780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6174111636).

3901557780 is an abundant number, since it is smaller than the sum of its proper divisors (8446665492).

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

3901557780 is a wasteful number, since it uses less digits than its factorization.

3901557780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21447 (or 21436 counting only the distinct ones).

The product of its (nonzero) digits is 264600, while the sum is 45.

The square root of 3901557780 is about 62462.4509605571. The cubic root of 3901557780 is about 1574.2704648548.

The spelling of 3901557780 in words is "three billion, nine hundred one million, five hundred fifty-seven thousand, seven hundred eighty".