38961990 has 48 divisors (see below), whose sum is σ = 102368448. Its totient is φ = 10280448.

The previous prime is 38961973. The next prime is 38961991. The reversal of 38961990 is 9916983.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (38961991) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6499 + ... + 10961.

It is an arithmetic number, because the mean of its divisors is an integer number (2132676).

Almost surely, 2^38961990 is an apocalyptic number.

38961990 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 38961990, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (51184224).

38961990 is an abundant number, since it is smaller than the sum of its proper divisors (63406458).

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

38961990 is a wasteful number, since it uses less digits than its factorization.

38961990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4573 (or 4570 counting only the distinct ones).

The product of its (nonzero) digits is 104976, while the sum is 45.

The square root of 38961990 is about 6241.9540209777. The cubic root of 38961990 is about 339.0109375958.

It can be divided in two parts, 3896 and 1990, that added together give a triangular number (5886 = T₁₀₈).

The spelling of 38961990 in words is "thirty-eight million, nine hundred sixty-one thousand, nine hundred ninety".